Test: Momentum Questions! Physics Trivia Quiz

Explanation
The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the truck has a mass of 6160 kg and is moving at a velocity of 3.00 m/s. Therefore, the momentum can be calculated as 6160 kg * 3.00 m/s = 18,480 kg*m/s.

Explanation
The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the mass of the car is given as 1540 kg and its velocity is given as 12.0 m/s. By multiplying these two values together, we get a momentum of 18,480 kg*m/s.

Explanation
The final velocity of the bicycle and student can be found using the equation v = u + at, where v is the final velocity, u is the initial velocity (which is 0 m/s since they are initially at rest), a is the acceleration, and t is the time interval. Given that the net force is 125 N and the total mass is 66 kg (55 kg + 11 kg), we can calculate the acceleration using the equation F = ma. Therefore, a = F/m = 125 N / 66 kg = 1.89 m/s^2. Plugging in the values into the equation v = u + at, we get v = 0 + 1.89 m/s^2 * 3.0 s = 5.68 m/s. Therefore, the final velocity of the bicycle and student is 5.68 m/s.

Explanation
The final velocity of an object can be calculated using the equation v = u + at, where v is the final velocity, u is the initial velocity (which is 0 in this case since the book is initially at rest), a is the acceleration, and t is the time. In this case, the net force of 10.0 N is causing the book to accelerate.

Using Newton's second law, F = ma, we can rearrange the equation to find the acceleration: a = F/m. Plugging in the values, a = 10.0 N / 3.0 kg = 3.33 m/s^2.

Now, we can calculate the final velocity using the equation v = 0 + (3.33 m/s^2) * (5.0 s) = 16.67 m/s. Therefore, the correct answer is 16.67 m/s.

Explanation
The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the ball has a mass of 0.15 kg and a velocity of 5.0 m/s. Multiplying these two values together gives us a momentum of 0.75 kg*m/s.

Explanation
The answer 6.25 m/s is correct because the question asks for the egg's initial speed. The net force exerted by the student is given as -1.5 N, which means it is in the opposite direction of the egg's motion. Using Newton's second law (F = ma), we can calculate the acceleration of the egg. The mass of the egg is given as 60.0 g, which is equivalent to 0.06 kg. The net force is -1.5 N, so we can rearrange the formula to solve for acceleration: a = F/m = -1.5 N / 0.06 kg = -25 m/s^2. Since the initial speed is the speed of the egg before it was brought to a stop, we can use the equation v = u + at, where u is the initial speed, a is the acceleration, and t is the time. Plugging in the values, we have 0 = u + (-25 m/s^2) * 0.25 s. Solving for u, we get u = 6.25 m/s.

Explanation
The question provides information about the force acting on the child and sled (75 N) and their combined mass (55 kg). To find their speed after 7.5 seconds, we can use the equation F = ma, where F is the force, m is the mass, and a is the acceleration. Rearranging the equation to solve for acceleration, we have a = F/m. Plugging in the given values, we get a = 75 N / 55 kg = 1.36 m/s^2. To find the speed, we can use the equation v = u + at, where v is the final velocity, u is the initial velocity (0 m/s since they are initially at rest), a is the acceleration, and t is the time. Plugging in the values, we get v = 0 + 1.36 m/s^2 * 7.5 s = 10.2 m/s. Therefore, the correct answer is 10.2 m/s.

Explanation
The total momentum of the child and the bike together can be calculated by multiplying the total mass of the system (child + bike) by their velocity. The mass of the child is 21 kg and the mass of the bike is 5.9 kg, so the total mass is 21 kg + 5.9 kg = 26.9 kg. The velocity of the system is given as 4.5 m/s. Therefore, the total momentum is 26.9 kg * 4.5 m/s = 121 kg*m/s.

Explanation
The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the mass of the child is 21 kg and the velocity is 4.5 m/s. Therefore, the momentum of the child can be calculated as 21 kg * 4.5 m/s = 94.5 kg*m/s. Since the answer choices are rounded to the nearest whole number, the correct answer is 95 kg*m/s.

Explanation
The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the mass of the bike is given as 5.9 kg and the velocity is given as 4.5 m/s. Therefore, the momentum of the bike can be calculated as 5.9 kg * 4.5 m/s = 26.55 kg*m/s. Rounded to the nearest whole number, the momentum of the bike is 27 kg*m/s.

Explanation
The impulse-momentum theorem states that the change in momentum of an object is equal to the impulse applied to it. In this case, the impulse is equal to the product of the braking force and the time interval. The braking force is 6250 N and the time interval is 2.5 s.

Using the formula for impulse, we can calculate the change in momentum:

Impulse = Force × Time
Impulse = 6250 N × 2.5 s
Impulse = 15625 N·s

Since momentum is equal to mass times velocity, we can rearrange the formula to solve for velocity:

Momentum = Mass × Velocity
Velocity = Momentum / Mass
Velocity = 15625 N·s / 2500 kg
Velocity = 6.25 m/s

Therefore, the car's velocity after 2.5 s is 6.25 m/s.

Explanation
The impulse-momentum theorem states that the change in momentum of an object is equal to the impulse applied to it. In this case, the impulse is equal to the product of the braking force and the time interval. The braking force is given as 6250 N and the time interval is given as 2.5 s. Therefore, the impulse is equal to (6250 N) * (2.5 s) = 15625 Ns.

Since the car is slowing down uniformly, the change in momentum is equal to the initial momentum minus the final momentum. The initial momentum is equal to the product of the car's mass and its initial velocity, which is (2500 kg) * (20.0 m/s) = 50000 kg*m/s. The final momentum is equal to zero because the car comes to a stop.

Therefore, the change in momentum is equal to 50000 kg*m/s - 0 kg*m/s = 50000 kg*m/s.

Using the impulse-momentum theorem, we can set the change in momentum equal to the impulse and solve for the distance traveled by the car.

50000 kg*m/s = 15625 Ns * t

Solving for t, we find t = 3.2 s.

The distance traveled is equal to the product of the initial velocity and the time interval, which is (20.0 m/s) * (3.2 s) = 64 m.

Therefore, the car moves a distance of 64 m during 2.5 s.

Explanation
The impulse-momentum theorem states that the change in momentum of an object is equal to the impulse applied to it. In this case, the car is being slowed down uniformly, so the change in momentum is equal to the initial momentum. The initial momentum of the car can be calculated by multiplying its mass (2500 kg) by its initial velocity (20.0 m/s), which gives 50,000 kg*m/s. The braking force acting opposite the car's motion is 6250 N. The impulse applied to the car can be calculated by multiplying the braking force by the time it acts for. Rearranging the formula for impulse, we can solve for time: impulse = force * time. Plugging in the values, we get 50,000 kg*m/s = 6250 N * time. Solving for time, we find that it takes 8 seconds for the car to come to a complete stop.