I think that in order for work to be done, the object must move in the direction of the force and move over a distance.
The blades that spin around in the fan, because they are flat and produce work
Answer:
160.75 N
Explanation:
The downward velocity has no effect on the force situation, it is only changes in velocity (plus, of course, gravity, which is always there) that require a force. At constant velocity, the bottom spring s_3 is supporting its mass m_3 to balance gravity.
As the elevator slows, though, it also ends up slowing down the spring arrangement, too. However, because the stretching takes time, it means that some damped harmonic motion will be set up in the spring chain.
When the motion has finally damped out, the net force the bottom spring s3 exerts on m3 has two components--that of gravity and of the deceleration of the elevator:
F_3net = m3 * (g + a) = 10.5×(9.81+5.5)= 10.5×15.31= 160.75 N
Answer:
Acceleration=
Speed=0.67 m/s
Explanation:
We are given that
Horizontal force=F=20 N
Mass of box=m=40 kg
We know that
Acceleration=
Using the formula
Acceleration of box=
The acceleration of the box=
Initial velocity=u=0
Force=F=30 N
Distance=s=0.3 m
Substitute the values
Hence, the speed of the box after it has been pulled a distance of 0.3 m=0.67 m/s