Question

a constant net force of 200 n is applied to accelerate a cart in a frictionless surface from rest to a velocity of 40 m/s in 10 s. what is the mass of the car?

Answer 1

Let's first find the acceleration of the cart:

$$a=\dfrac{v-v_0}{t}=\dfrac{40\ \dfrac{m}{s}}{10\ s}=4\ \dfrac{m}{s^2}.$$

Finally, we can find the mass of the cart from the Newton's Second Law of Motion:

$$m=\dfrac{F}{a}=\dfrac{200\ N}{4\ \dfrac{m}{s^2}}=50\ kg.$$