Physics, 24.12.2020 02:30, victory08

A tourist stands at the top of the Grand Canyon, holding a rock, overlooking the valley below. Find the final velocity and displacement of the rock after 4.0 seconds give the three initial conditions listed below: a. the rock is dropped vertically from rest
b. the rock is tossed vertically upward with 8.0m/s of speed
c. The rock is tossed vertically downward with 8.0 m/s speed

Answers: 3

Show answers

Answers

answered: amandapill

a. -39.2 m/s; -78.4 m

b. -31.2 m/s; -46.4 m

c. -47.2 m/s; -110.4 m

Explanation:

Part (a)

We are given/can infer these variables:

t = 4.0 sa = -9.8 m/s² v_0 = 0 m/s

We want to find the displacement and the final velocity of the rock.

Δx = ?v = ?

We can use this equation to find the final velocity:

v = v_0 + at

Plug in the known variables into this equation.

v = 0 + (-9.8)(4.0) v = -9.8 * 4.0 v = -39.2 m/s

The final velocity of the rock is -39.2 m/s.

Now we can use this equation to find the displacement of the rock:

Δx = v_0 t + 1/2at²

Plug in the known variables into this equation.

Δx = 0 * 4.0 + 1/2(-9.8)(4.0)² Δx = 1/2(-9.8)(4.0)² Δx = -4.9 * 16 Δx = -78.4 m

The displacement of the rock is -78.4 m.

Part (b)

We are given/can infer these variables:

v_0 = 8.0 m/sa = -9.8 m/s²t = 4.0 s

We can use this equation to find the final velocity:

v = v_0 + at

Plug in the known variables into this equation.

v = 8.0 + (-9.8)(4.0) v = 8.0 + -39.2 v = -31.2 m/s

The final velocity of the rock is -31.2 m/s.

We can use this equation to find the displacement:

Δx = v_0 t + 1/2at²

Plug in known variables:

Δx = 8.0(4.0) + 1/2(-9.8)(4.0)² Δx = 32 - 4.9(16)Δx = -46.4 m

The displacement of the rock is -46.4 m.

Part (c)

We are given/can infer these variables:

v_0 = -8.0 m/sa = -9.8 m/s²t = 4.0 s

We can use this equation to find the final velocity:

v = v_0 + at

Plug in the known variables into this equation.

v = -8.0 + (-9.8)(4.0) v = -8.0 - 39.2 v = -47.2 m/s

The final velocity of the rock is -47.2 m/s.

We can use this equation to find the displacement:

Δx = v_0 t + 1/2at²

Plug in known variables:

Δx = -8.0(4.0) + 1/2(-9.8)(4.0)²Δx = -32 - 4.9(16)Δx = -110.4 m

The displacement of the rock is -110.4 m.

answered: Guest

answerdmitry mendeleyev made a workable classification of the elements

answered: Guest

Answer(a) the matererials that are in contact, the two materials and the nature of their surfaces/// (b)/// the force pushing the two surfaces together, pushing the surfaces together causes the more of the asperities to come together and increases the surface area in contact with each other

Other questions on the subject: Physics

Physics, 21.06.2019 22:50, Jasten

A23 kg log of wood begins from rest, 300 m up a sluice (a water track used to transport logs, think of it as an inclined plane with negligible friction) inclined at 20° to the horizontal. after it reaches the flat waterway at the bottom it collides elastically with a 100 kg block of wood initially at rest near the base of the incline. (a) how long does it take the 23 kg log to travel down the incline? (b) what is the speed of the 23 kg log at the bottom of the incline? (c) what are the velocities of both blocks of wood after the collision? (d) what is the total kinetic energy before the collision? (e) what is the kinetic energy of the 23 kg log after the collision? (f) what is the kinetic energy of the 100 kg block of wood after the collision? (g) what is the total kinetic energy after the collision? (h) compare the total initial and total final kinetic energies. is this consistent with what you would expect for elastic collisions? explain!

Answers: 1

continue

Physics, 22.06.2019 00:30, aseel667789

Occurs when an energy source transfers heat directly to another subject space; an example would be an object becoming warm by sitting in the sunshine

Answers: 1

continue

Physics, 22.06.2019 01:00, tulensru02

Velocity is a description of both speed and direction, therefore it - a vector - a force arrow - the same as acceleration - a magnitude

Answers: 1

continue

Physics, 22.06.2019 01:30, ctomo2004

Ababy stroller is a rest on top of a hill which is 10 m high. the stroller and baby have a mass of 20 kg. what is the potential energy of the baby and stroller?

Answers: 1

continue

Do you know the correct answer?

A tourist stands at the top of the Grand Canyon, holding a rock, overlooking the valley below. Find...