Question

an apple of mass 444 g breaks loose of a tree and falls for 1.11 s before being caught by a person. the person’s hand is moved downward 9.99 cm by the apple as it is caught. (a) describe the action-reaction pairs of forces for the apple and the earth and for the apple and the hand. (b) find the amount that the earth (m

Answer 1

According to Newton's third law, the action-reaction pairs of forces for the apple and the earth are gravitational forces, while for the apple and the hand, they are normal forces. The earth's displacement due to the falling apple is negligible compared to the apple's displacement.

Step-by-step explanation:

According to Newton's third law, for every action, there is an equal and opposite reaction. In the case of the apple and the earth, the action-reaction pairs of forces are:

1. The apple exerts a gravitational force on the earth, and the earth exerts an equal and opposite gravitational force on the apple.
2. The apple exerts a normal force on the person's hand, and the hand exerts an equal and opposite normal force on the apple.

(a) The action-reaction pairs of forces for the apple and the earth are gravitational forces, while for the apple and the hand, they are normal forces.

(b) To find the amount that the earth moved, we can use the concept of conservation of momentum. Since the apple experienced a change in momentum while falling, the earth would experience an equal and opposite change in momentum. However, the mass of the earth is so large compared to the apple that its displacement is negligible.

Answer 2

The action-reaction pairs of forces for the apple and the Earth and for the apple and the hand are described using Newton's third law of motion. The mass of the Earth can be found using the equation F = ma, where F is the gravitational force, m is the mass, and a is the acceleration due to gravity.

Step-by-step explanation:

(a) According to Newton's third law of motion, for every action, there is an equal and opposite reaction. In the case of the apple and the Earth, the action-reaction pairs of forces are: the Earth exerts a gravitational force on the apple, and the apple exerts an equal and opposite gravitational force on the Earth. Similarly, for the apple and the hand, the action-reaction pairs of forces are: the hand exerts an upward force on the apple, and the apple exerts an equal and opposite downward force on the hand.

(b) To find the mass of the Earth, we can use the equation F = ma, where F is the gravitational force, m is the mass, and a is the acceleration due to gravity. Rearranging the equation, we get m = F / a. Substituting in the known values (force = mass × acceleration), we have m = (0.444 kg × 9.8 m/s²) / 9.8 m/s² = 0.444 kg.