Question

A car of mas 2000kg is driven with constant power P=1000w . Find the speed of the car (in m/s )at t=4s​

Answer 1

Answer:

I don't know answer of this question sorry

Answer 2

Given: A car of mas 2000kg is driven with constant power P = 1000W.

To find: The speed of the car at t = 4s​.

Solution:

• Power is ability to do work. It is the work done divided by time taken for the work to be done.

       $P = \frac{W}{t}$

• Work is the transfer of energy from one body to another. It is the product force and distance.

       $W = F * d$

• Hence, $P = \frac{F * d}{t}$

• Force is the product of mass and acceleration.

       $F = m * a$

• Hence, $P = \frac{m * a * d}{t}$

• Acceleration is the velocity divided by time.

        $a = \frac{v}{t}$

• Hence, $P = \frac{m * v * d}{t^{2} }$

        $1000W = \frac{2000kg * v * 1m}{4s}$

        $v = 2 ms^{-1}$

Therefore, the speed of the car (in m/s) at t=4s​ is 2ms⁻¹.