what is free fall ? give some example of it ?
Answer:
A free falling object is an object that is falling under the sole influence of gravity. Any object that is being acted upon only by the force of gravity is said to be in a state of free fall. ... Free-falling objects do not encounter air resistance.
Explanation:
please help im stuck
Answer:
1) B
2) B
Explanation:
1) because the relative atomic mass of zinc is 29 and it has a valence electron of 2+ charge.
2) Oxygen because it is has the second highest electronegativity and has a valence electron of-2 charge.
Answer:
1.b,2.b
Explanation:
Which statement best describes the movement of atoms in a solid?
O They are able to slide past each other.
O They spread apart as far as possible.
O They have no freedom to move.
O They are free to move in all directions.
Answer:
They have no freedom to move
Answer:
C
Explanation:
a car travelling east a constant speed of 20 metre per second be constructed at 3.8 metre per second square when it is 200 behind currently moving East at a constant speed of 2 metre per second how long will it take for the car to catch up with the truck how far will it truck and car travel during this time
Let, after t minutes car catch up with truck.
So, distance covered by car is, d = 200 + 2t.
Acceleration of car is, a = 2 m/s².
Initial velocity, u = 20 m/s.
Now, by equation of motion :
[tex]s =ut+\dfrac{at^2}{2}[/tex]
[tex]200+2t = 20t + \dfrac{2t^2}{2}\\\\t^2+18t -200=0[/tex]
[tex]t=\dfrac{-18\pm\sqrt{18^2-4(1)(-200)}}{2}\\\\t = \dfrac{-18\pm33.53}{2}\\\\t=7.765\ s[/tex]( eliminating negative solution )
Therefore, time required is 7.765 s.
a train travelled from city A to city B. For the first 14 hours, it travelled at an average speed of 120 km/h for the next 10 hours, it travelled at an average speed of 90km/h what was the average speed of the whole journey?
Answer:
107.5Explanation:
120 x 14= 1680 90 x 10= 900 Now you add 1680+900= 2580 Then you divide the distance (2580) between the speed (14+10) 2580/24= 107.5Philadelphia is 150 km south of New York City. With what constant velocity (km/hr) would a plane have to fly to go from New York to Philadelphia in 20 minutes?
Answer: 450km/h
Explanation:
A bumblebee is flying to the right when a breeze causes the bee to slow down with a constant leftward acceleration of magnitude 0.50 m s 2 0.50 s 2 m 0, point, 50, start fraction, start text, m, end text, divided by, start text, s, end text, squared, end fraction. After 2.0 s 2.0s2, point, 0, start text, s, end text, the bee is moving to the right with a speed of 2.75 m s 2.75 s m 2, point, 75, start fraction, start text, m, end text, divided by, start text, s, end text, end fraction. What was the velocity of the bumblebee right before the breeze? Give the correct sign for your answer, using a coordinate system where rightward is positive. Round the answer to two significant digits.
Answer:
3.75 m/s
Explanation:
Given that a bumblebee is flying to the right when a breeze causes the bee to slow down with a constant leftward acceleration of magnitude 0.50 m/s^2. After 2.0 s the bee is moving to the right with a speed of 2.75 m/ s
What was the velocity of the bumblebee right before the breeze?
Since the breeze blows with the acceleration of 0.5 m/s^2 for 2 seconds, we can calculate the magnitude of the velocity at which it moves.
Acceleration = velocity/ time
Substitute the acceleration and time into the formula
0.5 = V/2
Cross multiply
V = 2 × 0.5
V = 1 m/s
The bumblebee is travelling right ward while the wind travels leftward.
The relative velocity = 2.75 m/s
Let the bumblebee speed = Vb
While the wind = VW
Vb - Vw = 2.75
Substitute the wind speed into the formula
Vb - 1 = 2.75
Vb = 2.75 + 1
Vb = 3.75 m/s
Therefore, the velocity of the bumblebee right before the breeze is 3.75 m/s
A student starts at the origin and ends up at a position 500 meters north of the origin. She knows she walked 250 meters straight west, but then she was blindfolded and led to the final position. Assume she walked a straight path for the hidden leg of the trip. What displacement vector did she move?
Answer:
Explanation:
Displacement of the student will be gotten using pyhagoras theorem. Displacement is the distance covered in a specified direction.
D² = 500² + 250²
D = √500² + 250²
D = √250,000 + 62500
D = √312,500
D = 559.02metres
Hence the displacement vector of the girl is 559.02m
A piece of metal is 4 cm by 10 cm by 2
cm. Find its mass if it has a density of 2
g/cm^3
Answer:
m = 160 g
Explanation:
Density = Mass / Volume
D = m/v
Step 1: Define
D = 2 g/cm³
V = 4 cm · 10 cm · 2 cm = 80 cm³
M = ?
Step 2: Substitute and solve for m
2 g/cm³ = m/80 cm³
m = 160 g
why a soft floor is provided in wrestling
Answer:
dhsuf'jaeifnsf mndwqj'ofjef skjfgikef
Explanation:
Answer:
so that the wrestlers dont get a bad injury
Explanation:
A negative correlation___
is not a very considerate way to compute your numbers
means that as one variable goes up, the other goes down
is only used in experiments that test topics like depression or agression.
has no relationship among the variables
Which of the following correctly describes the relationship between speed and velocity?
Speed is the change in velocity over time; velocity is distance plus direction.
Speed is the change in distance over time; velocity is speed plus direction.
Speed is distance plus direction; velocity is speed plus time.
Speed is the change in acceleration; velocity is distance over time.
It is the second provided answer.
Speed is the change in distance over time; velocity is speed plus direction.
Vectors are unchanged if moved to another location as long as their length and direction remain unchanged
true or false
Jerrold just broke up with his girlfriend and is describing his current feelings about the breakup to his friend. According to Freud, from which part of Jerrold's mind did he pull the information to share? (2 points) Group of answer choices Unconscious Preconscious Conscious awareness Conscience
Answer:
Conscience
Explanation:
Conscience refers to a person's moral sense to differentiate between right and wrong to judge one's behaviour.
Jerrold just broke up with his girlfriend and is describing his current feelings about the breakup to his friend.
So, he pull the information from the conscience of Jerrold's mind.
A plane passes over Point A with a velocity of 8000 m/s north. Forty seconds later it passes over Point B at a velocity of 10,000 m/s north. What is the planes’ acceleration from A to B?
Answer:
The planes’ acceleration from A to B is 500m/s^2
Explanation:
Given that the initial velocity u is 8000m/s
and also given the final velocity v=10,000 m/s
the time taken to move from A to B = 40 second
The acceleration is defined as the rate of change of velocity with time
we know that the expression for acceleration is given as
a=(v-u)/t
substituting our given data into the expression for a we have
a=(10000-8000)/40
a=2000/40
a=500m/s^2
The planes’ acceleration from A to B is 500m/s^2
What does AC stand for in physics?
A. alternating current
B. alternative circult
C. alternating composition
D. all charge
Answer:
Alternating current
What happens when an object experiences friction?
A. Friction changes mechanical energy to heat energy
B. Friction changes mechanical energy to electrical energy.
C. Friction changes mechanical energy to pizza.
D. Friction changes mechanical energy to light energy
Answer:
its A. because since heat energy means thermal i think it is A and also When friction acts between two surfaces that are moving over each other, some kinetic energy is transformed into heat energy.
Explanation: your welcome and i hope its right
What type of energy is formed when chemical bonds are broken?
Light energy
Thermal energy
Chemical energy
Radiant energy
Answer:
Chemical
Explanation:
Just cuz
Answer:
Its chemical
Explanation:
I just took the quiz
Dominic is one of the tallest son of Mang Marco. He have a height of 180 cm and weight of 68 kg. find her BMI and weight status.
Answer:
BMI = 20.98 [kg/m^2]; Normal or Healthy Weight
Explanation:
Body mass index (BMI) is a person’s weight in kilograms divided by the square of height in meters. Therefore we must convert the height from centimeters to meters.
BMI = 68 / (1.8)^2
BMI = 20.98 [kg/m^2]
BMI Weight Status
Below 18.5 Underweight
18.5 – 24.9 Normal or Healthy Weight
25.0 – 29.9 Overweight
30.0 and Above Obese
So the weight status is Normal or Healthy Weight
Tsunamis are much different than rogue waves. While rogue waves are and other waves are generated by winds tsunamis originate from geological events such as movement of tectonic plates. Tsunamis tend to travel very fast. A tsunami generated off the coast of Chile in 1990 is estimated to have traveled approximately 6200 miles to Hawaii in 15 hours. Determine the speed in mi/hr and m/s. (Given: 1.0 m/s = 2.24 mi/hr)
Can you help me set up the problem and the numbers in the right place?
Answer:
410 mi/hr or 180 m/s
Explanation:
10
Design an experiment that can determine the relationship between
length of a pendulum and period (swingtime). Explain which variable is
dependent, which is independent, and list at least variables that will need
to be controlled. *
anyone know???
Answer:
Independent variable: length of pendulum
Dependent variable: period or swing time
Control variables: same mass of pendulum, point of release of each pendulum
Explanation:
This experiment involves determining the relationship between the length of a pendulum and period (swingtime) i.e. whether the length of the pendulum affected the period. In order to set up an experiment, pendulums with different lengths will be used. After the release of each pendulum, the swingtime or period (T) is measured.
- The independent variable is the variable that is changed or manipulated in the experiment. In this case, the independent variable is the LENGTH OF THE PENDULUM, which is changed for each pendulum.
- The dependent variable is the variable that is measured in an experiment. In this case, the PERIOD OR SWINGTIME is the dependent variable because it is what is measured.
- The controlled variable in an experiment is the variable that is kept unchanged for all the groups in an experiment. In this case, the MASS OF THE PENDULUM AND THE POINT OF RELEASE OF EACH PENDULUM are the control variables.
a car travelling at a velocity of 15ms -1 due north speeds up uniformly to a velocity of 30 ms -1 in 3 seconds. Calculate the acceleration.
Answer:
5 m/s²
Explanation:
Given:
v₀ = 15 m/s
v = 30 m/s
t = 3 s
Find: a
v = at + v₀
30 m/s = a (3 s) + 15 m/s
a = 5 m/s²
If you throw a ball up with a velocity of 3 m/s , how long will it take for the ball to reach the top of its path
Answer:
t = 0.306 s
Explanation:
Given that,
Initial velocity of the ball, u = 3 m/s
When it reaches the top of its path, its final velocity, v = 0
We need to find the time it takes the ball to reach the top of its path. It can be calculated using first equation of motion.
v = u +at
Here, a = -g
[tex]0=u-gt\\\\t=\dfrac{u}{g}\\\\t=\dfrac{3\ m/s}{9.8\ m/s^2}\\\\t=0.306\ s[/tex]
So, the ball will take 0.306 s to reach the top of its path.
You are in charge of designing a movie stunt for a new Fast and Furious film. In this scene a stunt person has to jump from a bridge and land on a boat in the water 22.5 m below. The boat is cruising at a constant velocity of 48.3 m/s towards the bridge. The stunt person will jump up at 6.45 m/s as they leave the bridge. You have to give them a cue for when to jump. How far from the bridge should the boat be at the moment the stunt person jumps?
Answer:
103.5 meters
Explanation:
Given that a stunt person has to jump from a bridge and land on a boat in the water 22.5 m below. The boat is cruising at a constant velocity of 48.3 m/s towards the bridge. The stunt person will jump up at 6.45 m/s as they leave the bridge.
The time the person will jump to a certain spot under the bridge can be calculated by using the formula below:
h = Ut + 1/2gt^2
since the person will fall under gravity, g = 9.8 m/s^2
Also, let assume that the person jump from rest, then, U = 0
Substitute h, U and g into the formula above
22.5 = 1/2 * 9.8 * t^2
22.5 = 4.9t^2
22.5 = 4.9t^2
t^2 = 22.5/4.9
t^2 = 4.59
t = [tex]\sqrt{4.592}[/tex]
t = 2.143 seconds
From definition of speed,
speed = distance /time
Given that the boat is cruising at a constant velocity of 48.3 m/s towards the bridge, substitute the speed and the time to get the distance.
48.3 = distance / 2.143
distance = 48.3 * 2.143
distance = 103.5 m
Therefore, the boat should be 103.5m away from the bridge at the moment the stunt person jumps?
What force is exerted on a ball of mass 100g if it accelerates from rest to 30 m/s in 3 seconds?
Force = mass * acceleration
acceleration = change in velocity / time taken
Answer:
[tex]a \: force \: \boxed{f} \: of \: \boxed{ 1N}[/tex]
Explanation:
[tex]given : \\ mass \: \boxed{m} = 100g = 0.1kg \\ velocity \: \boxed{v} = 30 {m(s)}^{ - 1} \\ time \: \boxed{t} = 3sec \\ .......................................................... \\ f = ma = \frac{mv}{t } \\ f = \frac{0.1 \times 30}{3} \\ \boxed{f = 1 \: N}[/tex]
♨Rage♨
Q.1. What determines the rate at which energy is delivered by a current ?
Explanation:
The rate of consumption of electric energy in an electric appliance is called electric power. Hence, the rate at which energy is delivered by a current is the power of the appliance.
which of these can a force acting on a object not change ?
A direction of motion B state of rest
C Shape D mass
D)Mass
Hope it helps (:
B.F. Skinner is best known for the development of _____.
Answer:
the theory of behaviorism
Explanation:
i looked it up¯\_(ツ)_/¯
_______ is taking what you have observed and expressing it as a number.
Answer: measurement
How do you find Net Force?
Answer:
Net force is the total amount of force acting on an object when you take into account both magnitude and direction.[1] An object with a net force of zero is stationary. An unbalanced force, or net force of a magnitude greater than or less than zero, leads to acceleration of the object.[2] Once you have calculated or measured the magnitude of a force, combining them to find the net force is simple. Sketching a simple force diagram and making sure all of the forces are labelled and in the correct direction makes calculating net force a breeze.
Explanation:
