A 12.0-kg box is being pushed from the bottom to the top of a frictionless ramp. When the box is pushed at a constant velocity, the non-conservative pushing force does 58.0 J of work. How much work is done by the pushing force when the box starts from rest at the bottom and reaches the top of the same ramp with a speed of 1.50 m/s

work done = 71.5 J

Explanation:

Given that,

Energy = Fifty eight J

Mass of box = 12.0 Kg

Speed = 1.5 m/s

U = work done

The external force acts solely on the box and also the earth system. conjointly note that the work done by external force

= modification of energy of the system

U = work done - K

Also recall that the box is moving with constant speed therefore, there will not be modification in acceleration, hence, there'll be no modification in K.E..

Therefore, K is adequate to zero.

K= 0

U = work done = energy

U = 58.0 J

work done by pushing force = K + U

work done = final K.E. - initial K.E. + U 1

Initial K.E. = zero

Substitute the mandatory values into equation one

work done = 1/2m v² - zero + U

work done= 0.5 x 12.0 x 1.5² + 58.0

= 13.5+58.0

work done = 71.5 J

The world one by the pushing force is 71.5 J

when it gains or loses electrons

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.