7. a force of 100 n acting on a body gives it a speed of 200 m/s in 2
sec. what is the mass of the body?
a. 1kg
b. 5 kg
c. 10kg
d. 15kg

Choice a. 1 kg, assuming that all other forces on the object (if any) are balanced.

Explanation:

By Newton's Second Law,

,

where

As a result,

.

Assume that all other forces on this object are balanced. The net force on the object will be . The net force is constant. Acceleration should also be constant and the same as the average acceleration in the two seconds.

.

.

.

e

explanation:

there is no change in the electric potential energy as it is in rest on both conditions.

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.