Two toy cars can roll without friction on a horizontal surface. car a is a 5 kg. car b is 0.5 kg. both cars start from rest. equal sized forces are used to push each cart forward for a time of 1 second. after 1 second the force is removed. what is the difference in magnitude of the momenta of the two cars, right after the force is removed? choices: a. the momentum of car a(5kg) is equal to that of car b(0.5)b. the momentum of car a (5kg) is less than that car b (0.5)c. the momentum of car a (5kg) is more than that car b (0.5)d. 5.5 kg m/s

A. The momentum of car A(5kg) is EQUAL to that of car B(0.5)

Explanation:

The moment, or impulse formula of the same forces acting on both car within 1 second is

In our case the forces are the same, the time duration of force acting on the cars are the same. Therefore, their momentum right after the force must also be the same.

b. lifting dumbbell weight at 20-degree angle from the body after a 45-degree angle

air exerts forces on falling objects near earth’s surface.

explanation:

the term 'free falls' refer to object that are falling towards the earth, in a situation in which gravity is the only force acting on the object.

for an object in free fall, the acceleration is constant (g, the gravitational acceleration), and so the velocity of the object constantly increases.

for objects near earth's surface, there is always another force acting on the object: the resistance due to the air. this force is opposed to the direction of fall of the object, and it is proportional to the velocity of the object, so as the object falls down, this force increases up to a point when it balances the force of gravity, and the object continues its motion at constant velocity (called terminal velocity). since in this case gravity is not the only force acting on the object, we are not in a situation of free fall.