An empty truck weighing 4 tons began to move with an acceleration of 0.3 m / s.

An empty truck weighing 4 tons began to move with an acceleration of 0.3 m / s. What is the mass of the load taken by the car if, with the same traction force, it starts off with an acceleration of 0.2 m / s.

Data: m (weight of the empty truck) = 4 t; a1 (acceleration of an empty truck) = 0.3 m / s2; the pulling force is constant; a2 (vehicle acceleration with a load) = 0.2 m / s2.
Since the traction force of a truck is constant, the mass of the cargo can be determined from the equality: m * a1 = F = (m + mg) * a2, whence m + mg = m * a1 / a2 and mg = m * a1 / a2 – m …
Let’s make the calculation: mg = 4 * 0.3 / 0.2 – 4 = 6 – 4 = 2 tons.
Answer: The car received a load of 2 tons.