Question

An astronaut in space throws an object away from his space shuttle. Which of the following statements is true?

• A. The initial velocity of the astronaut is equal and opposite to the velocity of the tool.
• B. The impulse applied to the astronaut is equal and opposite to the impulse applied to the tool.
• C. The mass of the astronaut is equal to the mass of the tool.
• D. The momentum of the astronaut is greater than the momentum of the tool.
• E. The force applied to the tool is greater than the force applied to the astronaut.

Answer 1

The correct option is B The impulse applied to the astronaut is equal and opposite to the impulse applied to the tool.

From Newton's third law of motion, a reaction force acts on the astronaut equal in magnitude and opposite in direction to the force acted on the object.
Since they would take same amount of time to acts,

$\int Fdt=\int Rdt$

$⟹I_1=I_2$

Hence impulses on both are same in magnitude and opposite in direction.