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
astraxan [27]
3 years ago
14

The normal force acting on an object and the force of static friction do zero work on the object. However the reason that the wo

rk is zero is different for the two cases. Explain why each does zero work.
Physics
1 answer:
spin [16.1K]3 years ago
3 0

Answer:

<em>The normal force is perpendicular to the displacement</em>

<em>The static friction force produces no displacement</em>

Explanation:

Work Done By Special Forces

The work is a physical magnitude that measures the dot product of the force applied to an object by the displacement it produces in it.

W=\vec F\ \vec r

It can be written in its scalar version as

W=F.d.cos\theta

Being F and d the magnitudes of the force and displacement, and \theta the angle between them

If the angle is zero, the work is at maximum, it the angle is 90°, the work is zero. If the angle is between 90° and 180°, the work is negative.

The normal force acts in the vertical direction when the object is being pushed horizontally. It means the angle between the force and the displacement is 90°, thus the work is

W=N.d.cos90^o=0

The work is zero because the force and the displacement are perpendicular

The static friction force exists only when the object is being applied a force of a magnitude not large enough to produce movement, i.e. the object is at rest. If the object is moved, the friction force is still present, but it's called dynamic friction force, usually smaller than the static.

Since in this case, there is no displacement, d=0, and the work is

W=F_r(0)cos180^o=0

You might be interested in
What is the acceleration of a baseball that has a final velocity of 15.0 m/s when it crosses the plate 2.0 seconds after leaving
Leokris [45]
I think it’s A pretty sure...
3 0
3 years ago
Is 5g greater than 20.43 mg
worty [1.4K]

yes that's true 6g is larger

4 0
3 years ago
Read 2 more answers
Two children who are bored while waiting for their flight at the airport decide to race from one end of the 20-m-long moving sid
QveST [7]

Answer: Phillipe wins the race

Explanation:

Given

Length of track=20 m

Velocity of Phillippe=2 m/s w.r.t sidewalk

Velocity of sidewalk=1.5 m/s

Rena velocity=2 m/s

Therefore absolute velocity of P is 2+1.5=3.5 m/s

Time taken by phillippe \frac{20}{3.5}+\frac{20}{3.5-1.5}

t_P=5.714+10=15.714 s

Time taken by rena

t_r=\frac{20}{2}+\frac{20}{2}=20 s

as the time taken  by phillippe is less than rena therefore Phillippe wins the race.

8 0
3 years ago
Read 2 more answers
A swimmer bounces almost straight up from a diving board and falls vertically feet first into a pool.she starts with a speed of
garik1379 [7]

Answer:

a) 1.20227 seconds

b) 0.98674 m

c) 7.3942875 m/s

Explanation:

t = Time taken

u = Initial velocity = 4.4 m/s

v = Final velocity

s = Displacement

a = Acceleration due to gravity = 9.81 m/s²

v=u+at\\\Rightarrow 0=4.4-9.81\times t\\\Rightarrow \frac{-4.4}{-9.81}=t\\\Rightarrow t=0.44852\ s

s=ut+\frac{1}{2}at^2\\\Rightarrow s=4.4\times 0.44852+\frac{1}{2}\times -9.81\times 0.44852^2\\\Rightarrow s=0.98674\ m

b) Her highest height above the board is 0.98674 m

Total height she would fall is 0.98674+1.8 = 2.78674 m

s=ut+\frac{1}{2}at^2\\\Rightarrow 2.78674=0t+\frac{1}{2}\times 9.81\times t^2\\\Rightarrow t=\sqrt{\frac{2.78674\times 2}{9.81}}\\\Rightarrow t=0.75375\ s

a) Her feet are in the air for 0.75375+0.44852 = 1.20227 seconds

v=u+at\\\Rightarrow v=0+9.81\times 0.75375\\\Rightarrow v=7.3942875\ m/s

c) Her velocity when her feet hit the water is 7.3942875 m/s

3 0
3 years ago
At what wavelength would a star radiate the greatest amount of energy if the star has a surface temperature of 60,000 K?
kompoz [17]

Answer:

\lambda=4.81\times 10^{-8}\ m

Explanation:

We have,

The surface temperature of the star is 60,000 K

It is required to find the wavelength of a star that radiated greatest amount of energy. Wein's displacement law gives the relation between wavelength and temperature such that :

\lambda T=2.89\times 10^{-3}

Here,

\lambda = wavelength

\lambda=\dfrac{2.89\times 10^{-3}}{60000}\\\\\lambda=4.81\times 10^{-8}\ m

So, the wavelength of the star is 4.81\times 10^{-8}\ m.

7 0
3 years ago
Other questions:
  • Four students measured the acceleration of gravity. The accepted value for their location is 9.78 m/s2. Which student's measurem
    9·2 answers
  • What does a plant use in photosynthesis and what are the products? <br><br> PLEASE HELP:)
    14·1 answer
  • Two astronauts (each with mass 100 kg) are drifting together through space. They are connected to each other by a rope 5 m in le
    10·1 answer
  • A load of 5.0N stretches a spring by 10cm the relaxed length is 40cm assuming that the proportional length is not exceeded deter
    11·1 answer
  • Help with this question please
    14·1 answer
  • What state has the longest coast
    9·1 answer
  • Two clouds collide and form another, more massive cloud. One cloud is stationary, while the other is traveling at 1 m/s. After t
    9·1 answer
  • What will happen in the particles of liquid after 12 hours inside the freezer?​
    7·1 answer
  • SOMEONE PLEASE HELP MEEEEEEE
    8·1 answer
  • A go cart with a mass of 60 kg is moving at a rate of 10 m/s. How much Kinetic Energy does the go cart have?
    13·2 answers
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!