Forces and motion：練習問題

A runner moves at a constant speed of \( 3 \text{ m/s} \). Calculate the distance they travel in \( 2 \text{ minutes} \).

A force of \( 15 \text{ N} \) is applied to a spring, causing it to extend by \( 0.25 \text{ m} \). Calculate the spring constant, \( k \).

A car of mass \( 1200 \text{ kg} \) accelerates from rest to \( 30 \text{ m/s} \) in \( 6 \text{ seconds} \). Calculate the resultant force acting on the car.

Which of the following is a scalar quantity?

A car travels along a straight road. It accelerates from \( 10 \text{ m/s} \) to \( 22 \text{ m/s} \) in a time of \( 4 \text{ seconds} \). Calculate the acceleration of the car.

A student uses a newtonmeter to measure the weight of an object. State the relationship between the weight and the mass of an object.

A car of mass \( 1200\text{ kg} \) is travelling at a constant velocity. Calculate the resultant force acting on the car and explain your answer using Newton's First Law.

A student pushes a crate across a rough floor with a horizontal force of \( 40 \text{ N} \). If the crate moves a distance of \( 5 \text{ m} \) at a constant speed, calculate the work done by the student and state the energy transfer occurring due to friction.