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3 years ago

Give an example to explain that motion is relative in nature

1 answer:

3 0

Consider a long train moving at speed v. Now consider a passenger throwing a ball inside this train, towards the back of the train, with same velocity v (but in the opposite direction of the train movement).

- A passenger inside the train will see the ball moving with speed v
- For an observer outside the train, however, the ball will appear as still. In fact, for him the ball will have a speed v (given by the movement of the train) -v (velocity of the ball but moving in the opposite direction), so the net velocity will be v+(-v)=0.

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ASAP Is a phone sliding down a binder potential and kinetic energy.

NemiM [27]

Kinetic energy because there is motion (PE converting to KE). Potential energy is the amount of stored energy.

6 0

3 years ago

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A speed-time graph shows a car moving at 10 m/s for 10 s. The cars speed constantly decreases until it comes to a stop at 30 s.

Ray Of Light [21]

speed of the car at t = 10 s is given as 10 m/s

now at t = 30 s car comes to rest so v = 0

now in this velocity time graph we can say slope will show the acceleration of the car as we know that acceleration is rate of change in velocity

$a = \frac{v_f - v_i}{\Delta t}$

as we know that

$v_f = 0$

$v_i = 10 m/s$

$\Delta t = (30 - 10) = 20 s$

now from above formula

$a = \frac{0 - 10}{20} = -0.5 m/s^2$

So slope of the graph will represent the acceleration of car which is 0.5 m/s^2

5 0

3 years ago

Read 2 more answers

At an amusement park, a swimmer uses a water slide to enter the main pool. a. If the swimmer starts at rest, slides with negligi

adoni [48]

Answer:

a)6.7m/S

b)6.8m/s

Explanation:

Hello ! To solve the point b you must follow the steps below

1.Draw the slide taking into account its length and height and find the angle from which the swimmer is launched (see attached image)

2. Find the horizontal velocity (X) and vertical (Y) components (see attached image)

3) for the third step we must remember that as in the slide there is no horizontal acceleration the speed in X will remain constant at the end of the swimmer's path (Vx = 0.59m / s)

the fourth step is to remember that vertically there is constant acceleration called gravity (g = 9.81m / s ^ 2), so to find the speed at the end of the route we use the following equation

$Vfy= \sqrt{Vy^2+2gy}$

where

Vfy= final verticaly speed

Vy=initial verticaly speed=0.59m/S

g=gravity=9.81m/S^2

y=height of slide=2.31m

solving

$Vfy= \sqrt{Vy^2+2gy}\\Vfy= \sqrt{(0.59)^2+2(9.81)(2.31)}=6.77m/s$

The last step is to add the velocity components vectorally at the end of the route with the following equation

$V=\sqrt{Vfy^2+Vx^2} =\sqrt{6.77^2+0.59^2} =6.8m/s$

point A

taking into account the previous steps we can infer that as the swimmer starts from rest, the velocity (Vx=Vy=O) is zero, so we should only use the formula for constant acceleration movement.

$Vfy= \sqrt{Vy^2+2gy}$

vy=0

$Vfy=\sqrt{2gy}$

Vfy= $\sqrt{2(9.81)(2.31)}$ =6.7m/s

8 0

3 years ago

Which statement is true of a mechanical wave?

svet-max [94.6K]

It must have a medium. It must travel in empty space. Mechanical waves are waves which needs medium of propogation.

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1 year ago

What does a lunar eclipse and a solar eclipse have in common

liraira [26]

During either one, the sun, moon, and Earth are lined up in the same straight line. The difference is whether the moon or the Earth is the one in the "middle".

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3 years ago