# Answer on Mechanics | Relativity Question for Sam

Question #5516

a 100 kg car pullin a 500 kg trailer accelerates at a rate of 2 m/s. if the frictional force on the trailer is 1000N, with what force does the car pull the trailer? with what force does the trailer pull the car?

Expert's answer

Let's make following denotations:

m = 100 kg

M = 500 kg

a = 2 m/s^2

Fr = 1000N

Accordingly to the trird Newton's law, the trailer pull the car with the same force as the car pull the trailer. Now let's use the second Newton's law:

m*a = M*a + Fr.

100*2 = 500*2 + 1000, but 200 <> 2000.

We see that the second Newton's law is failed. The problem has impossible conditions.

m = 100 kg

M = 500 kg

a = 2 m/s^2

Fr = 1000N

Accordingly to the trird Newton's law, the trailer pull the car with the same force as the car pull the trailer. Now let's use the second Newton's law:

m*a = M*a + Fr.

100*2 = 500*2 + 1000, but 200 <> 2000.

We see that the second Newton's law is failed. The problem has impossible conditions.

## Comments

## Leave a comment