Question

Can someone tell me some numericals on laws of motion with answers



ACCORDING TO CLASS 9​

Answer 1

Calculate the force needed to speed up a car with a rate of 5ms–2, if the mass of the car is 1000 kg.

Solution: According to question:

Acceleration (a) = 5m/s2 and Mass (m) = 1000 kg, therefore, Force (F) =?

We know that, F = m x a

= 1000 kg x 5m/s2

= 5000 kg m/s2

Therefore, required Force = 5000 m/s2 or 5000 N

Question 2: If the mass of a moving object is 50 kg, what force will be required to speed up the object at a rate of 2ms–2?

Solution: According to the question;

Acceleration (a) = 2ms–2 and Mass (m) = 50 kg, therefore, Force (F) =?

We know that, F = m x a

= 50 kg x 2m/s2

= 100 kg m/s2

Therefore, required Force = 100 m/s2 or 100 N

Question 3: To accelerate a vehicle to 3m/s2 what force will be needed if the mass of the vehicle is equal to 100 kg?

Solution: According to the question:

Acceleration (a) = 3m/s2 and Mass (m) = 100 kg, therefore, Force (F) =?

We know that, F = m x a

= 100 kg x 3m/s2

= 300 kg m/s2

Therefore, required Force = 300 m/s2 or 300 N

Answer 2

A train starting from a railway station and moving with uniform acceleration attains a speed 40Km/hr in 10minutes .find acceleration.