Grade 11 Newton Laws QUESTION


A tow truck is towing a car using an inelastic steel cable (of negligible mass) as shown in the diagram below. The steel cable forms an angle of 30° with the horizontal.

The two vehicles move from rest on a straight, horizontal road to the right. The mass of the car is 1100 kg and the mass of the tow truck is 4000 kg. The tow truck’s engine applies a force of 15 000 N. A constant frictional force of 1456 N is acting on the car and a constant frictional force of 4520 N is acting on the tow truck respectively.

3.1 State Newton’s Second Law of motion, in words. (2)

3.2 Draw a labeled, free-body diagram of all the forces acting on the car. (4)

3.3 Calculate the:

3.3.1 acceleration of the car. (6)

3.3.2 magnitude of the tension T in the cable. (3)

3.5 Using equations of motion, calculate the distance that the car will travel in 4s. (2)

3.6 State Newton’s First Law of motion, in words. (2)

3.7 Use Newton’s laws of motion to explain why towing can be dangerous. (2)

3.8 If the force of horizontal tension in the cable, from the car on the truck, is 1890 N, what is the horizontal force of the truck on the car? Explain with reference to the relevant scientific principles. (2) [23]



Paper shared with the help KC Kakinda


Resolving vectors into components and calculating resultant

GRADE 11 P2 MARCH 2020