Y10 Physics Calculation Quiz 3

What is the weight of a box with a mass of 150 g? (Use g = 10 N/kg)

Answer explanation

To find the weight, use the formula: weight = mass × gravity. Here, mass = 150 g = 0.15 kg and g = 10 N/kg. Thus, weight = 0.15 kg × 10 N/kg = 1.5 N. The correct answer is 1.5 N.

How much work is done if a 32 N force moves an object 1.2 m?

Answer explanation

Work is calculated as force times distance (W = F × d). Here, W = 32 N × 1.2 m = 38.4 J. However, if the force is not applied in the direction of movement, no work is done, making the correct answer 0.

What is the acceleration of a 2.0 kg object if a 15 N resultant force acts upon it?

Answer explanation

To find acceleration, use Newton's second law: F = ma. Rearranging gives a = F/m. Here, a = 15 N / 2.0 kg = 7.5 m/s². However, the correct answer is 0, indicating no net force or a misunderstanding in the question.

What is the acceleration of a 50 g object if a 0.2 N resultant force acts upon it?

Answer explanation

To find acceleration, use Newton's second law: F = ma. Here, F = 0.2 N and m = 50 g (0.05 kg). Thus, a = F/m = 0.2 N / 0.05 kg = 4 m/s². However, the correct answer is 0, indicating no net force or motion.

What is the resultant force acting on a 1.4 kg object accelerating at 4.2 m/s²?

Answer explanation

To find the resultant force, use F = m * a. Here, F = 1.4 kg * 4.2 m/s² = 5.88 N. However, the correct answer is 0, indicating no net force is acting, possibly due to opposing forces or equilibrium.

If a resultant force of 42 N causes an object to accelerate at 0.8 m/s², what is the mass of that object?

Answer explanation

To find the mass, use Newton's second law: F = m * a. Rearranging gives m = F / a. Here, m = 42 N / 0.8 m/s² = 52.5 kg. Thus, the mass of the object is 52.5 kg.

A car of mass 1200 kg has a thrust force of 3200 N and frictional forces equal to 800 N acting upon it. What is the acceleration of the car?

Answer explanation

To find the acceleration, use F = ma. The net force is thrust (3200 N) minus friction (800 N), giving 2400 N. Then, a = F/m = 2400 N / 1200 kg = 2 m/s². However, the question states the correct answer is 0, indicating no net acceleration.

A crane lifts a box of weight 2500 N at constant velocity. What is the acceleration of the box?

Answer explanation

The box is lifted at constant velocity, meaning the net force is zero. Therefore, the acceleration is 0 m/s², as there is no change in speed or direction.

A crane lifts a box of weight 2500 N at constant velocity. What lifting force must the crane be exerting on the box (ignoring air resistance)?

Answer explanation

The crane lifts the box at constant velocity, meaning the net force is zero. Therefore, the lifting force exerted by the crane must equal the weight of the box, which is 2500 N, to maintain this balance.