Work = Force multiplied by the distance(or displacement)
Answer:
Train will take 156 sec to travel 12km.
Answer:
Answered
Explanation:
A) The work done by gravity is zero because displacement and the gravitational force are perpendicular to each other.
W= FS cosθ
θ= 90 ⇒cos90 = 0 ⇒W= 0
B) work done by tension
W= Tcosθ×S= 5cos30×2.30= 10J
C) Work done by friction force
W= f×s=1×2.30= 2.30 J
D) Work done by normal force is Zero because the displacement and the normal force are perpendicular to each other.
E) The net work done= Work done by tension in the rope - frictional work
=10-2.30= 7.7 J
Answer:
Speed of cart's might be less than the high speed after 5 seconds.
Explanation:
Given that,
A fan cart with the fan set to high rolled across the floor.
Let the speed of fan cart with set to high is
per second.
The fan supplies a force to the cart. If a lower fan speed were used, less force would be applied. This would cause a slower change in the cart's speed. So, the cart would be rolling more slowly than
per second after 5 seconds. The speed of cart's might be less than
per second.
Force is needed
A. for a moving object to keep moving at the same speed and direction
B. for a moving object to change its speed
C. for a motionless object to remain still
D. to prevent a moving object from turning
Hence,
Speed of cart's might be less than the high speed after 5 seconds.