Answer:
answer a
Explanation:
while any machine is working, there are some forces (f.e. friction) that are still calculating.
Good luck
you toss a ball straight upward so it leaves your hand at a speed of 10.1 m/s. if the 3.3 kg ball started at rest and the tossing action lasted 0.33 s, what was the strength of the force exerted on the package by your hand?
The strength of the force exerted on the package by your hand: 101 N
We know v = u+at
v =10.1 m/s
u = 0
t =0.33 s
10.1 = 0+a*0.33
10.1 = a*0.33
a = 30.6 m/s^2
Force exerted F = ma
= 3.3*30.6
= 101
F = 101 N
What is Force ?A force is an effect that can change the motion of an object. Under the influence of a force, an object with mass can change its speed (e.g. move from standstill), i.e. to speed up A force can also be intuitively described as a push or a pull. A force has both magnitude and direction, so it is a vector quantity. It is measured in SI units Newton (N). Power is represented by the symbol F (formerly P).
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a car of mass 1689 kg collides head-on with a parked truck of mass 2000 kg. spring mounted bumpers ensure that the collision is essentially elastic. if the velocity of the truck is (in the same direction as the car's initial velocity) after the collision, what was the initial speed of the car?
If the velocity of the truck is (in the same direction as the car's initial velocity) after the collision, The initial speed of the car is 18.565 km/h.
Let the initial velocity of the car be uc
the truck is parked it implies ut = 0
for a head on elastic collision the final velocities are given by
[tex]vc = - (mt - mc/mt + mc) uc[/tex]
[tex]vt = (2mc/mt + mc)uc[/tex]
Velocity (vt) = 17 Km/hr
uc = 18.565 Km/hr
In physics, a collision, which is also known as an impact, is the abrupt, violent coming together in close proximity of two bodies, such as two pool cues, The force and the amount of time the objects are in touch, in addition to the materials the two objects are made of, have an impact on the outcome of the impact. It is generally knowledge that a hard steel ball dropped on a steel plate would rebound almost to the original position from where it was dropped, while a ball made of putty or lead will not.
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which statements are true, concerning jupiter as compared to the other planets in our solar system? (may be more than one correct answer)
Out of all the planets, Jupiter has the most mass. Of all the planets, Jupiter has the strongest magnetic field. Of all the planets, Jupiter rotates the most quickly.
Jupiter rotates most quickly where?With a rotational velocity of 28,273 miles per hour (or 43,000 kilometers per hour), Jupiter's equator rotates a little more quickly than its polar regions. Jupiter's day ranges from 9 hours, 56 minutes near the poles to 9 hours, 50 minutes towards the equator. As the largest planet, Jupiter has the gravitational ability to draw in the most mass as it travels through space, making it the planet with the quickest rotation. Jupiter acquires the angular momentum of whatever mass it comes into contact with, including gas, dust, and rock, in addition to the mass itself. One rotation of Jupiter, for instance, takes 9 hours and 55 minutes, although it rotates at a speed that is 27 times quicker than Earth's at its equator.
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One force that acts on a surfer is friction. Another is gravity. Which of these is a non-contact force?
Answer: gravity
Explanation:
Friction requires 2 surfaces in contact with each other. Gravity is a non-contact, universal force.
A truck is traveling clockwise around a circular track at a constant speed of 10 m/s.
The track is flat and has a radius of 100 m. While driving around the track, the driver
is describing his experience to his driving coach:
"The whole time I'm traveling around the track, I feel like I'm being pushed to the left
even though I'm constantly turning right. I'm always leaning toward the outside of
the circle."
Which best explains the Physics concept of why the driver felt this?
The best suitable answer is Option 4 " The driver experienced centrifugal "force" which was actually just his inertia .
What is centrifugal force ?
A hypothetical force called centrifugal force, which is unique to particles travelling in a circle, is a force that has the same strength and dimensions as the centripetal force, but acts in the opposite direction.
A stone rotating in a horizontal plane while attached to a string that is fastened to a ground-based post experiences a constant change in velocity and acceleration in the direction of the post. The square of the speed divided by the length of the string gives us the acceleration.
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In order for work to be done on an object, the force must be in the same direction as the object moves. true or false?
Answer:
True
Explanation:
because in science work is only said to be done when the body moves through the distance of the force applied
A block of mass m1 = 14.4 kg is on a frictionless table to the left of a second block of mass m2 = 20.2 kg, attached by a horizontal string (see the figure below).
(a) If a horizontal force of 1.53 ✕ 102 N is exerted on the block m2 in the positive x-direction, use the system approach to find the acceleration (in m/s2) of the two blocks.
(b) What is the tension (in N) in the string connecting the blocks?
(a) The acceleration (in m/s²) of the two blocks is 4.42 m/s².
(b) The tension (in N) in the string connecting the blocks is 63.65 N.
What is the acceleration of the blocks?
The acceleration of the blocks is determined by applying Newton's second law of motion as shown below.
F(net) = ma
where;
F(net) is the net force on the blocksm is the mass of the blocksa is the acceleration of the blocksF = m₁a + m₂a
F = a(m₁ + m₂)
a = F/(m₁ + m₂)
where;
a is the common acceleration of the blocksm₁ is the mass of the first block = 14.4 kgm₂ is the mass of the second block = 20.2 kgF is the applied force on the blocks = 153 Na = (153) / (14.4 + 20.2)
a = 4.42 m/s²
The tension (in N) in the string connecting the blocks is calculated as follows;
T = m₁a
T = 14.4 x 4.42
T = 63.65 N
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A 1.5 kg ball is kicked with an initial velocity of 26 m/s at an angle of 30 degrees above the horizontal. How far did the ball go before returning to the ground? Answer in meters.
The maximum height travelled by the ball before returning to the ground is 8.62 m.
What is the maximum height travelled by the ball?
The maximum height travelled by the ball before returning to the ground is calculated by applying the following kinematic equation as shown below.
H = (u²sin²θ) / 2g
where;
u is the initial velocity of the ballθ is the angle of projection of the ballg is acceleration due to gravityH = (26² (sin 30)²) / (2 x 9.8)
H = 8.62 m
Thus, the maximum height travelled by a projectile depends on the initial velocity and angle of projection.
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A 100.0 g arrow is pulled back 30.0 cm against a bowstring. The bowstring's spring constant is
1250 N/m. What speed will the arrow have when it leaves the bowstring if the arrow is shot horizontally?
Velocity of the arrow while leaving the bow is 33.54 m/s.
What is kinetic energy?Kinetic energy is the energy that an object has when it is in motion. If you want to accelerate an object you have to apply a force. To add strength, we need our work. When the work is done, the energy is transferred to the object and it moves at a new constant speed.
Energy stored in the string = Kinetic energy of the arrow.
1/2(ke²) = 1/2(mv²)
Where k = spring constant of the bowstring
e = extension
m = mass of the arrow
v = velocity of the arrow.
Let's make v the subject of this equation
v = √(ke²/m)
Given: k = 1250 N/m
e = 30 cm or 0.3 m
m = 100 g or 0.1 kg
Substitute the values into the equation:
v = √(1250×0.30²/0.1)
v = √(1125)
v = 33.54 m/s
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Calculate the initial velocity of a ball thrown vertically into the air reaching a maximum
height of 20 m. (Don't forget: at maximum height the final velocity is zero and the
acceleration is -10 m/s²)
The initial velocity of the ball thrown vertically into the air reaching a maximum height is 20 m/s.
What is velocity?
Velocity can be defined as the ratio of displacement to time.
To calculate the initial velocity of the ball, we use the formula below.
Formula:
v² = u²+2gh............... Equation 1Where:
v = Final velocityu = Initial velocityg = Acceleration due to gravityh = HeightFrom the question,
Given:
v = 0 m/sg = -10 m/s²h = 20 mSubstitute these values into equation 1
0² = u²+[2×20×(-10)]-u² = -400u² = 400u = √400u = 20 m/sHence, the initial velocity of the ball is 20 m/s.
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a hot air balloon is rising vertically with a velocity of 10.0 feet per second. a very small ball is released from the hot air balloon at the instant when it is 1280 feet above the ground. use a(t)
the final velocity of the hot air balloon before touching the ground is 286.16 ft/s.
the final velocity can be calculated as follows:
initial velocity of the sphere, u = 10 ft/s
Acceleration due to gravity, g = 32 ft/s²
Ground clearance, h = 1280 feet
The time it takes for the ball to hit the ground is calculated as:
[tex]h= ut +\frac{1}{2}gt^2\\ 1280= 10t + (0.5X 32 )t^2\\1280 = 10t +16t^2\\16t^2+ 10t-960 = 0[/tex]
then we can solve the quadratic equation using formula method
[tex]t=\frac{ -b+/- \sqrt{b^2-4ac} }{2a} \\t = \frac{ -10+/- \sqrt{10^2-4(16X1280)} }{2(16)}\\t= 8.63[/tex]
The final velocity of a hot air balloon is calculated as:
v = u + gt
v = 10 + (8.63 × 32)
v = 286.16 ft/sec
therefore, the final velocity of the hot air balloon before touching the ground is 286.16 ft/s.
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betelgeuse is a red giant. this means the star is nearing the end of its life, and becoming larger and redder in the process. what's happening to the surface of the star as it becomes redder?
For a solar mass star, the red-giant phase normally lasts just around a billion years overall, with practically all of that time being spent on the red-giant branch.
The phases of horizontal branch and asymptotic huge branch move ten times more quickly.After a star exhausts its hydrogen fuel for nuclear fusion and starts to die, a red giant develops. A star keeps itself stable by carefully balancing the forces of its own gravity, which holds it together, with the pressure exerted outward by continuing thermonuclear fusion reactions occurring at its core.The typical lifespan of red giant stars is between 0.1 and 2 billion years. Red giant stars are significantly less massive and smaller than red supergiant stars.To know more about red-giant
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if the blocks are released from rest, which way does the 10 kgkg block slide, and what is its acceleration? enter a positive value if 10 kgkg block accelerates up the ramp, and a negative value otherwise.
The acceleration is -0.48m/s².
Explain what an acceleration is.Acceleration is the rate of change in both speed and direction of velocity over time. Anything is said to have been accelerated when it goes faster or slower in a straight line.
Suppose that θ=35°
First, you need to set up equations for both blocks.
Let m₁ be 10kg and m₂ be 5kg and for our computations suppose right is positive and up is positive
For m₁ the solution is:
Sigma Fx = ma
T - m₁gsin35 = m₁a
where T = tension
For m₂
m₂g - T = m₂a
Add the two equations together
m₁a + m₂a = T-m₁gsin35 + m₂g - T
a(m₁ + m₂) = m₂g - m₁gsin35
a= (5×9.8 - 10×9.8×sin35)/(10 + 5)
a= -0.48m/s².
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A TV with the power rating of 200 Watt uses 0.8 kilowatt of electrical energy in one day. For how many hours was the TV on during this day?
The number of hours that the TV was on is four hours.
What is the number of hours that the TV was on?We know that is possible to calculate the cost of electricity and this is done when we convert the electricity to the billing unit that we call the kilowatt hour.
Now we know that;
Power rating of the TV = 200 watt or 0.2 KW
The amount of electricity that was used by the TV in a day = 0.8 KWh
We can now find the number of hours from the relation;
Power rating * time = Energy used
0.2 * t = 0.8
t = 0.8/0.2
t = 4 hours
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An object i aid to be poitively charged if it number of electron i greater than the number of proton
An object I aid to be positively charged if it has a number of electrons i greater than the number of protons. TRUE
If an object has extra protons than electrons, then the internet fee on the item is fantastic. If there are extra electrons than protons, then the net charge at the item is bad. If there are equal numbers of protons and electrons, then the object is electrically impartial.
An electrical price is created while electrons are transferred to or removed from an object. because electrons have a bad charge, while they are added to an item, it turns negatively charged. when electrons are removed from an object, it will become undoubtedly charged.
A positively charged object has misplaced electrons. A definitely charged object has won protons. A negatively charged item has lost protons. If the variety of electrons is greater than the range of protons, the particle is a negative ion, also referred to as an anion.
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Disclaimer:- your question is incomplete, please see below for the complete question.
An object I aid to be positively charged if it has a number of electrons i greater than the number of a proton. TRUE/FALSE
true or false: if an elevated feature near the heel or flanks or a position upwind of the fire affords a good sight line, take advantage of it as long as there is zero possibility that the fire will go there.
An elevated feature near the heel or flanks or a position upwind of the fire affords a good sight line and there is advantage of it as long as there is zero possibility that the fire will go there, which is true statement.
Elevated feature helps to protect the space besides there is a fire present. Elevated feature is the safest and nearest place to not get effected by the fire present in the other side of the elevated feature.
This feature is also created in case of emergency situations to immediately reduce the effect of the fire. This could a technique to reduce the effect of the hazards in the disaster management.
While considering the effect of hazards reduction, there are parameters on which these depends, are shape of elevated feature, elevation of the elevated feature and steepness of the elevated feature.
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A 1,286-kg car is skidding to a stop along a horizontal surface. The car decelerates from 26.9 m/s to rest in 9.36 seconds. How far did the car skid before coming to rest?
Answer:
Explanation:
Given:
M = 1 260 kg
V₀ = 26.9 m/s
V = 0 m/s
Δt = 9.36 s
___________
L - ?
1)
Vehicle acceleration:
a = (V - V₀) / Δt ) = (0 - 26.9) / 9.36 ≈ - 2.87 m/s²
2)
Braking distance of the car:
L = (V² - V₀²) / (2·a)
L = ( 0² - 26.9²) / (2·(-2.87)) ≈ 121 m
an automobile of mass 1500kg moving at 25.0m/s collides with a truck of mass 4500kg at rest. this time, the car and the truck bounce off each other completely elastically. what is the final velocity of the car (in m/s) after the collision? call the initial direction of the automobile positive.
the final velocity of the car (in m/s) after the collision is 6.25 m/s
12.5 m/s is moving in the initial direction of the car
1. A car of mass 1500 kg moving at a speed of 25.0 m/s collides with a truck of mass 4500 kg at rest. the bumpers of both vehicles lock on impact.
A. Compare the force exerted by the car on the truck with the force exerted by the truck on the car during the collision. Is one force greater than the other, or are they equal in magnitude?
the force exerted by the car on the truck and the force exerted by the truck in the collision.
creates a pair of actions and reactions
are equal in magnitude and opposite in direction according to Newton's third law
b. What is the final speed of the car and the truck just after the collision? show your calculations.
v=m1u1+m2u2/m1+m2=1500*25+0/1500+4500=6.25 m/s
2. the same collision as in the above question occurs, but this time the car and truck bounce off each other completely elastically.
C. Compare the force exerted by the car on the truck with the force exerted by the truck on the car in the collision. is one force greater than the other or are they equal?
the force exerted by the car on the truck and the force exerted by the truck in the collision.
creates a pair of actions and reactions
are equal in magnitude and opposite in direction according to Newton's third law
d. what is the final speed of the car and truck just after the collision?
view the calculation
v1=[m1-m2/m1+m2]u1+[2m2/m1+m2]u2=[1500-4500/6000]*25+[9000/6000]*0=-12.5 m/s
a negative sign means the car is moving backwards at 12.5 m/s
v2=[m2-m1/m1+m2]u2+[2m1/m1+m2]u1=[4500-1500/6000]*0+[3000/6000]25=12.5 m/s
moves in the original direction of the car
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cords of connective tissue that connect MUSCLES TO BONES
Answer:
Tendon
Explanation:
Tendons are a type of connective tissue that attach muscle to bone. Hope this helps! :)
Describe the motion of a hockey puck between the instant the puck leaves a player's stick and the instant it hits something. (No "slap shot" allowed, the puck must remain in contact with the ice.)
Answer:
Explanation:
it will have constant friction, or slowing, as it slides along the ice.
an astronaut weighs 99 n on the moon, where the acceleration of gravity is 1.62 m/s2. how much does she weigh on earth? group of answer choices 600 n 440 n 61 n 16 n 99 n
On the moon, where gravity accelerates at 1.62 m/s2, an astronaut weighs 99 n, but their weight on Earth is 600 Newton(option a is correct).
Work done = Mass * Acceleration due to gravity
99=m*1.62
m=61.11kg
W=mg 61.11*9.8=598.89N = 600N= Weight on Earth
The acceleration of an item refers to the pace at which its velocity with respect to time varies. The number of accelerations in a vector (in that they have magnitude and direction). An object's acceleration in respect to a net force is determined by the direction of that force. Newton's Second Law states that the combined effects of two elements determine how much an item accelerates:
The amount of this net resultant force is exactly proportional to the size of the net balance of all external forces operating on that item. Depending on the materials used in construction, mass and mass are inversely connected.
Acceleration is measured in meters per second squared (m/s2).
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if the ball is traveling at 140 km/h just before it reaches the bat, what is the magnitude of the average force exerted by the bat on it if the collision lasts 7.0 ms ?
To find the collision rate, known the magnitude.
What is magnitude?
Magnitude typically refers to size or distance. By comparing the size and motion speed of the thing, we can relate magnitude to movement. The object's or quantity's size determines its magnitude.
What is mean by collision rate?
The frequency of collisions between a single particle of radius m and particles with masses ranging from (m1, m1 + m1) to (m, m1) is proportional to their concentration, n(m1) m1, where (m, m1) is the rate constant for collisions between the two particles of masses m and m1 and depends on the process.
u=140kmph
t=7.oms
v=0
E=M(V-U)/t
⇒m(0-140)/0.007×5/18m/s
⇒5555.55 (m) N
E=(5555.55) (mass) N
Therefore, the collision lasts is 5555.55(m) N.
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How large a net force is required to accelerate a 2000-kg suv from rest with an acceleration of 0. 14 m/s2?.
Answer:
280 N
Explanation:
Remember F = ma
F = 2000 * .14 = 280 N
A 2.5 newton weight falls freely from rest from the roof of a building. What is the total distance the weight falls in the first 4.0 seconds?
Answer:
Explanation:
L = g·t² / 2 = 9.8·4.0² / 2 = 78.4 m
a bus traveled 387 km in 5 h.one hour of the trip was in city traffic. the bus's city speed was just half of its speed on open highway. the rest of the trip was on open highway. find the bus'scity speed
The bus'scity speed is 77.4km/hr.
How is speed defined in?What constitutes speed? the speed of a change in an object's position in any direction.
Speed is the rate of change in location of an item, expressed in meters per second. If something starts at the origin and goes three meters in three seconds, for instance, its speed is one meter per second. Like distance divided by time, the equation for speed is straightforward.
A change in an object's position over time is referred to as motion in physics. Displacement, distance, velocity, acceleration, time, and speed all play a role in how motion is defined. Speed is a scalar variable that describes how quickly an object travels through space with regard to time.
speed = distance/time
speed =387/5
speed =77.4km/hr.
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calculate the height (in m) of a cliff if it takes 2.21 s for a rock to hit the ground when it is thrown straight up from the cliff with an initial velocity of 8.01 m/s. (enter a number.) (b) how long (in s) would it take to reach the ground if it is thrown straight down with the same speed? (enter a number.)
The height of the cliff is 6.22 meters and the time taken by the rock to hit the ground if thrown with same speed is 0.81 seconds.
The time taken by the rock to hit the ground when it is thrown up from the the cliff with an initial velocity of 8.01 m/s.
(a) From the equation of motion,
H = ut+1/2at²
H is the height of the cliff,
u is the the initial velocity,
t is the time taken by the rock,
g is the acceleration due to gravity.
Putting values,
H = (8.01)(2.21) + 1/2(-9.8)(2.21)²
H = -6.22m.
The height of the cliff is 6.22 m.
(b) If the rock is thrown down with the same speed,
Then the time taken by it to reach the ground is,
t = u/g
Putting values,
t = 8.01/9.8
t = 0.81 seconds.
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what is the magnitude of its angular velocity, in radians per second, after a 23 kg child gets onto it by grabbing its outer edge? the child is initially at rest.
The magnitude of the angular velocity of the merry-go-round is equal to 2.39 rad/s after a 23 kg child gets onto it.
What is angular momentum?Angular momentum can be described as the rotational form of linear momentum. It is a physical conserved quantity as the total angular momentum remains constant.
Given, the mass of the child m = 23 Kg
The mass of the merry-go-round M = 125 Kg
The initial speed of the merry-go-round, ω₁ = 0.52 rev/s = 3.27 rad/s
The radius, r = 1.8 m
From the conservation of the angular momentum, we can find the angular velocity:
[tex]I_1\omega_1= (I_1+mr^2)\omega[/tex]
[tex](\frac{1}{2} Mr^2)\omega_1= (\frac{1}{2} Mr^2+mr^2)\omega[/tex]
[tex]\omega =\frac{M.\omega_1}{M+2m}[/tex]
[tex]\omega = \frac{125\times 3.27}{125 +2\times23}[/tex]
ω = 2.39 rad/s
Therefore, the magnitude of its angular velocity after a 23 kg child gets onto it by grabbing its outer edge is 2.39 rad/s.
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Your question was incomplete, but the most probably complete question was,
A playground merry-go-round with a mass of 125 Kg and a radius of 1.8 m is rotating with a frequency of 0.52 rev/s. what is the magnitude of its angular velocity, in radians per second, after a 23 kg child gets onto it by grabbing its outer edge? the child is initially at rest.
a crane lowers a metal beam into place at constant speed. which is true about the work done by the gravitational force (wg) and the work done by the tension in the cable (wt) as the beam is lowered? a) wg>0 and wt>0 b) wg>0 and wt<0 c) wg<0 and wt>0 d) wg<0 and wt<0 e) wg
The work done by gravitational force and tension in the cable is wg > 0 and wt <0. option 2 is correct.
The work done by the force is given as :
W = Fdcosθ
where
F= force
d = displacement
θ = angle between directions of F and d
when force and displacement are parallel then :
θ = 0
cosθ = ±1
so work done is positive
when force and displacement are anti-parallel then :
θ = 180°
cosθ = -1
so work done is negative.
then crane is moving downward. the force is also downward and tension is upward.
The work done by gravitational force and tension in the cable is wg > 0 and wt <0. option 2 is correct.
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at what wavelength of light to humans give off the most light if the average human body temperature is approximately 310 k?
Peak thermal radiation for the human body at 310 K has a wavelength of 9.3 mm.
The average body temperature is 310.15 oK. The infrared region is where the radiation peaks as a result. Red light with wavelengths as long as 7,000 Angstroms can be seen by the human eye. Generally speaking, infrared wavelengths are those between 7,000 and 1,000,000 Angstroms.
Light's wavelength is used to measure it (in nanometers). It is typically represented by the Greek letter. Visible light is typically defined as having a wavelength between 400 and 700 nanometers (nm), or one billionth of a meter.
The distance between equivalent places in two consecutive light cycles is known as the wavelength of light, and the frequency of light is the number of light cycles that pass a specific spot in a second.
Atoms or molecules that undergo discrete energy level transitions give rise to narrowband radiation.
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In addition to being insanely adorable, the Klipspringer is known to jump 3.6 meters straight up in the air (that is several times their body height). What is the initial upward velocity required to make this happen?
Answer:
Explanation:
Given:
H = 3.6 m
V = 0 m/s
g = 9.8 m/s²
_________
V₀ - ?
Potential energy = m·g·H
Kinetic energy = m·V₀² / 2
Let's equate:
m·V₀² / 2 = m·g·H
V₀² / 2 = g·H
Starting speed:
V₀ = √ ( 2·g·H )
V₀ = √ (2·9.8·3.6) ≈ 8.4 m/s
