1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Tpy6a [65]
3 years ago
5

A 95.0kg weightlifter pushes on a 800,000 kg wall for 400s but it does not move. How much work does he do on the wall?

Physics
1 answer:
Soloha48 [4]3 years ago
7 0
<span>The weightlifter does no work. Although he has exerted force, work is the product of force over distance. Since he has not moved the wall he has done no work.</span>
You might be interested in
What was the major shortcoming of rutherford’s model of the atom?
lisabon 2012 [21]

The major shortcoming of Rutherford's model was that it was incomplete. It did not explain how the atom's negatively charged electrons are distrubuted in the space surronding its positively charged nucleus. A form of energy that exhibits wavelike behavior as it travels through space

7 0
3 years ago
An airplane flies in a loop (a circular path in a vertical plane) of radius 160 m . The pilot's head always points toward the ce
notka56 [123]

Answer:

a) 39.6 m/s b) 4123 N

Explanation:

a) At the top of the loop, all of the forces point downwards (force of gravity and normal force).

Fnet=ma

ma=m(v^2/R) (centripetal acceleration)

mg=m(v^2/R)

m cancels out (this is why pilot feels weightless) so,

g=(v^2/R)

9.8 m/s^2 = v^2/160 m

v^2=1568 m^2/s^2

v=39.6 m/s

b) At the bottom of the loop, the normal force and the force of gravity point in opposite directions. The normal force is the weight felt.

Convert 300 km/hr to m/s

300 km/hr=83.3 m/s

Convert pilot's weight into mass:

760 N = 77.55 kg

Fnet=ma

n-mg=m(v^2/R)

n=(77.55 kg)(((83.3 m/s)^2)/160 m)+(77.55 kg)(9.8 m/s^2)

n=3363.2 N+760 N=4123 N

5 0
2 years ago
Find the final velocity
Verizon [17]

Answer: v = 4.4 m/s

Explanation:

In the absence of friction, the total mechanical energy will be constant

KE₀ + PE₀ = KE₁ + PE₁

0 + mg(6) = ½mv₁² + mg(5)

½mv₁² = mg(6 - 5)

v = √(2g(1)) = 4.4 m/s

3 0
2 years ago
The wavelength of a wave on a string is 1.2 meters. If the speed of the wave is 60 meters/second, what is its frequency?
maria [59]
F=v/wavelength f=1.2/60=50Hz.
8 0
2 years ago
Read 2 more answers
A cat jumps from 2.5-meter-tall bookshelf to a 1.3-meter-tall countertop. If the cat
UkoKoshka [18]

The change in Potential energy of the cat is 176.4 J.

<h3 /><h3>Potential Energy:</h3>

This is the energy due to the position of a body. The S.I unit is Joules (J)

The formula for change in potential energy.

<h3 /><h3>Formula:</h3>
  • ΔP.E = mg(H-h).............. Equation 1

<h3>Where:</h3>
  • ΔP.E = Change in potential energy
  • m = mass of the cat
  • g = acceleration due to gravity
  • H = First height
  • h = second height.

From the question,

<h3>Given:</h3>
  • m = 15 kg
  • H = 2.5 m
  • h = 1.3 m
  • g = 9.8 m/s²

Substitute these values into equation 1

  • ΔP.E = 15×9.8(2.5-1.3)
  • ΔP.E = 15×9.8×1.2
  • ΔP.E = 176.4 J.

Hence, The change in Potential energy of the cat is 176.4 J

Learn more about Potential energy here: brainly.com/question/1242059

5 0
2 years ago
Other questions:
  • What is the force that opposes the movement of an object through water??
    5·2 answers
  • When resting, a person has a metabolic rate of about 3.0 105 joules per hour. The person is submerged neck-deep into a tub conta
    13·1 answer
  • Which pair of countries are both part of the crib Caribbean cultural regions in North America
    12·1 answer
  • A coach wants her team to have fun, win some games, and be a productive unit. What is the most important personality trait the c
    8·2 answers
  • When should you use a piece of pipe as a leverage extension on the handle on a wrench?
    5·1 answer
  • What is the same about the EM categories? What is different?
    15·1 answer
  • Which statements accurately describe Dmitri Mendeleev’s contributions to the development of the periodic table? Check all that a
    13·2 answers
  • Chris shoots an arrow up into the air. The height of the arrow is given by the function h(t) = - 16t2 + 64t + 23 where t is the
    7·2 answers
  • What are magnetic materials
    12·1 answer
  • If the same total travel at the speed of 0.05 m/s for 40 seconds, how far would it have gone?
    10·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!