Final answer:
The force that the astronaut exerts on his chair while sitting at rest on the launch pad is equal to the force of gravity acting on him, which can be calculated using the formula F = mg.
Step-by-step explanation:
The force that the astronaut exerts on his chair while sitting at rest on the launch pad can be determined using Newton's second law of motion, which states that force is equal to mass multiplied by acceleration. Since the astronaut is at rest, the net force acting on him is zero. Therefore, the force he exerts on the chair is equal in magnitude but opposite in direction to the force of gravity acting on him.
The force of gravity can be calculated using the formula F = mg, where F is the force of gravity, m is the mass of the astronaut, and g is the acceleration due to gravity. In this case, the mass of the astronaut is 64 kg and the acceleration due to gravity is approximately 9.8 m/s².
Using the formula F = mg, the force of gravity acting on the astronaut is 64 kg * 9.8 m/s² ≈ 627.2 N. Therefore, the astronaut exerts a force of 627.2 N on his chair while sitting at rest on the launch pad.