How much work is required to make a 1400 kg car increase its speed from 10 m/s to 20 m/s?

7000J

Explanation:

Given parameters:

Mass of car  = 1400kg

Initial speed  = 10m/s

Final speed  = 20m/s

Unknown:

Amount of work done  = ?

Solution:

In this problem, the amount of work done is the same as the change in kinetic energy of the body.

So;

   Work done  = Final kinetic energy  - initial kinetic energy

           Kinetic energy  =  m v²

   Work done  =  m(V²f - V²i )

m is the mass

vf is the final velocity

vi is the initial velocity

   Work done  =   x 1400 x (20 - 10)  = 7000J

a electromagnetic waves

the answer is f1 and d2 because if you put equal force on those two points the beam would balance trust me on this