Answer:
A or D
Explanation:
Net force includes addition or subtraction.
Answer:
1. It may change the direction of an object in motion.
2. It may cause change in velocity of an object in motion.
Explanation:
1.It may change the direction of an object in motion.
When an object is in motion,an applied force on that object may change its direction.
For example, a sailboat moving eastward, can suddenly change its direction by interaction of a storm wind blowing form the south.
2. It may cause change in velocity of an object in motion .
A force applied to an object in motion can increase or decrease its speed. When the force is applied to the object in motion in the direction of that object, its velocity may increase.
On the other hand, when the force is applied in the opposite direction to the object in motion, its velocity may reduce.
Answer:
The tension in the string is quadrupled i.e. increased by a factor of 4.
Explanation:
The tension in the string is the centripetal force. This force is given by

m is the mass, v is the velocity and r is the radius.
It follows that
, provided m and r are constant.
When v is doubled, the new force,
, is

Hence, the tension in the string is quadrupled.
Answer:
Potential Energy to Kenetic Energy
Explanation:
When holding a ball in the air, the ball has potential energy. Once you drop the ball, the ball gains Kenetic Energy