Question

A boy pulls a car of mass m=20 kg by a cord with constant force F= 200 N at an angle of 37∘, the normal force in (N) is:

A. None of the above
B. 110
C. 80
D.0.92

Answer 1

The normal force is calculated by subtracting the vertical component of the pulling force from the gravitational force on the car. The options provided do not include the correct normal force value of 76 N; hence the correct answer is option A 'None of the above'.

Step-by-step explanation:

The student is asking how to find the normal force exerted on a car when it is pulled by a cord at an angle. To solve for the normal force, we need to consider the forces acting in the vertical direction. The force of gravity acting on the car is mg, where m is the mass of the car and g is the acceleration due to gravity (9.8 m/s²). The vertical component of the pulling force must also be considered; it is Φ (the force at the angle, F) times the sine of the given angle (sin(37°)). The normal force is the force exerted by the surface to support the weight of the car and balance the vertical component of the pulling force. Therefore, the normal force equation is:

N = mg - Fsin(θ)

Substituting the given values we get:

N = (20 kg)(9.8 m/s²) - 200 N × sin(37°)

Calculating this, we find that the normal force, N, equals 196 N - 120 N, which is 76 N.

The correct answer, however, does not appear in the given options, therefore, the correct choice would be 'A. None of the above'.