1. Two astronauts are playing catch with a ball in space. The first astronaut throws the ball; and
A. the ball doesn’t move, but the astronaut does.
B. the ball moves, and so does the astronaut.
C. the ball doesn’t move, and neither does the astronaut.
2. Newton's second law states that F = m x a (Force is mass times acceleration). Which example would have the GREATEST acceleration?
A. a 50 kg student launched by a 100 Newton catapult
B. a 500 kg car accelerated by 1000 Newtons from the engine
C. a 10 kg ball thrown with a 50 Newton force
3. According to Newton's Third Law, what is the equal and opposite force to the downward force of gravity pulling on a man standing on the beach?
A. the force of friction holding the man still
B. the man pulling upward on the earth
C. the surrounding air pressure keeping the man in equilibrium
please help
1. The correct answer is B. the ball moves, and so does the astronaut. In space, without any external forces acting on them, both the ball and the astronaut will move in opposite directions due to the conservation of momentum. When the first astronaut throws the ball, they exert a force on the ball, causing it to accelerate away from them. In response, according to Newton's third law of motion, the ball exerts an equal and opposite force on the astronaut, causing them to move in the opposite direction.
2. To determine which example would have the greatest acceleration, we need to compare the force applied to each object and their respective masses. The acceleration is calculated by dividing the force by the mass (a = F/m).
A. For the 50 kg student launched by a 100 Newton catapult:
Acceleration = 100 N / 50 kg = 2 m/s²
B. For the 500 kg car accelerated by 1000 Newtons from the engine:
Acceleration = 1000 N / 500 kg = 2 m/s²
C. For the 10 kg ball thrown with a 50 Newton force:
Acceleration = 50 N / 10 kg = 5 m/s²
Therefore, the example with the greatest acceleration is C. the 10 kg ball thrown with a 50 Newton force.
3. According to Newton's third law of motion, for every action, there is an equal and opposite reaction. In this case, the downward force of gravity pulling on a man standing on the beach would have an equal and opposite force. The correct answer is B. the man pulling upward on the earth. The man exerts an upward force on the Earth due to gravity, which is equal in magnitude to the downward force of gravity on the man. This demonstrates Newton's third law of motion.