2a. Consider a hand holding a ball at rest. The ball weighs 10 N. The forces acting on the ball are its weight and the force of the hand on the ball. The forces acting on the hand are the weight of the hand and the force exerted by the ball on the hand.
How big is the reaction force associated with the weight of the ball? What object is responsible for that force?
How big is the force that the ball exerts on the hand? How big is the reaction force associated with this force?
Now let the hand exert a 15 N force on the ball.
How big is the reaction force associated with the weight of the ball? What object is responsible for that force?
How big is the force that the ball exerts on the hand? How big is the reaction force associated with this force?
2006-09-17 16:13:40 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Physics
First off - if the ball is held motionless, the forces are opposite and equal. The upward force of the hand is exactly equal to the downward force of the ball. There are no unequal forces (they cancel each other out) and the ball will remain stationary.
If the hand should exert a larger force (15N) against the 10N ball - the forces are then unequal and the ball will move in an upward direction.
In essence, the ball now has a differential upward force of 5N applied to it.
Note: motion will only occur when a force is applied or when two or more forces of unequal magnitude are applied.
2006-09-17 16:24:04 · answer #1 · answered by LeAnne 7 · 0⤊ 0⤋
10 newtons... it is in equilibrium.. the force pulling down is gravity... the force up is exerted by the hand add 15 to the hand and the force is upward
2006-09-17 23:18:40 · answer #2 · answered by wizard 4 · 0⤊ 0⤋