Question

The engine of a car delivers a constant power of P to the wheels. The resistive forces are
constant at all speeds. The maximum speed that the car can achieve on a level road is v.
If the car is going at v/3, the net force acting on the car is
(A) P/v
(B) 2P/v
(C) 3P/v
(D) zero​

Answer 1

Answer:

itz option d

hope this will helps u....

@ItzSugaryHeaven3

Answer 2

Given: The engine of a car delivers a constant power of P to the wheels. The resistive forces are constant at all speeds. The maximum speed that the car can achieve on a level road is v. The car is going at v/3.

To find: The net force acting on the car.

Solution:

• The rate of doing work by an agent, or a machine, is called the power of the agent, or the machine.
• The power of an agent is the dot product of the force applied to a body and the velocity produced in the body.
• This is represented by the following formula.

       $P = Fv$

• When the car is going at the speed v/3,

       $P = F * \frac{v}{3}$

• On rearranging, the net force acting on the car is found to be,

        $F = \frac{3P}{v}$

Therefore, the net force acting on the car is 3P/v.