1.
Momentum has
Correct Answer
C. Magnitude and direction
Explanation
Momentum is a vector quantity that describes the motion of an object. It has both magnitude and direction. The magnitude of momentum is determined by the mass and velocity of the object, while the direction is determined by the direction of the velocity. Therefore, momentum has both magnitude and direction.
2.
Momentum = mass x force
Correct Answer
B. False
Explanation
The given statement, "Momentum = mass x force," is incorrect. The correct equation for momentum is momentum = mass x velocity. Momentum is the product of an object's mass and its velocity, not force. Therefore, the correct answer is false.
3.
When objects become tangled or stick together it is called an __________________collision.
Correct Answer
inelastic
Explanation
When objects become tangled or stick together after a collision, it is referred to as an inelastic collision. In an inelastic collision, kinetic energy is not conserved, and the objects involved deform or stick together due to the transfer of momentum. This type of collision is commonly observed in real-life scenarios, such as car accidents or objects colliding and becoming entangled.
4.
Elastic collision is
Correct Answer
B. Objects that collide and bounce off of each other
Explanation
In an elastic collision, two objects collide and bounce off of each other, without any loss of kinetic energy. This means that both objects retain their individual velocities after the collision. This is in contrast to an inelastic collision, where objects collide and stick together, resulting in a decrease in their combined velocity. Therefore, the correct answer is "objects that collide and bounce off of each other."
5.
What is the momentum of a 15-kg rock rolling at 3 m/s?
Correct Answer
C. 45 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 rock is given as 15 kg and its velocity is given as 3 m/s. Multiplying these values together gives us a momentum of 45 kg m/s.
6.
A 50 kg Corvette (car) has a momentum of 500 kg m/s. How fast is the car going?
Correct Answer
B. 10 m/s
Explanation
The momentum of an object is calculated by multiplying its mass by its velocity. In this case, the momentum of the car is given as 500 kg m/s and its mass is given as 50 kg. To find the velocity, we can rearrange the equation and solve for it. Dividing the momentum by the mass, we get a velocity of 10 m/s.
7.
A bowling ball has 9 kg m/s of momentum when it is rolled 6 m/s. What is the mass of the bowling ball?
Correct Answer
D. 1.5 kg
Explanation
The momentum of an object is calculated by multiplying its mass and velocity. In this case, the momentum of the bowling ball is given as 9 kg m/s and its velocity is given as 6 m/s. To find the mass of the bowling ball, we can rearrange the formula for momentum to solve for mass. Dividing the momentum (9 kg m/s) by the velocity (6 m/s), we get a mass of 1.5 kg.
8.
If your dog pulls the rope with 15 N force to the right and you pull the rope 5 N force to the left. What is the force and direction in Newtons of the final motion?
Correct Answer
B. 10 Newtons to the right
Explanation
When the dog pulls the rope with a force of 15 N to the right and you pull the rope with a force of 5 N to the left, the net force is calculated by subtracting the force to the left from the force to the right. Therefore, the net force is 15 N - 5 N = 10 N to the right.
9.
Which of the following is a way to decrease momentum?
Correct Answer
B. Increase friction
Explanation
Increasing friction is a way to decrease momentum because friction opposes the motion of an object. When friction is increased, it creates a force that acts in the opposite direction of the object's motion, resulting in a decrease in its momentum. Therefore, increasing friction can slow down or stop the object, ultimately decreasing its momentum.
10.
What is the momentum of a Hummer with a mass of 2000 kg traveling at a velocity of 20 km/h?
Correct Answer
A. 40,000 kg km/h
Explanation
The momentum of an object is calculated by multiplying its mass and velocity. In this case, the Hummer has a mass of 2000 kg and is traveling at a velocity of 20 km/h. By multiplying these two values, we get a momentum of 40,000 kg km/h.
11.
How does wearing a seatbelt reduce your chance of getting hurt during an accident?
Correct Answer
B. Seatbelts reduce momentum during a collision
Explanation
Seatbelts reduce momentum during a collision by restraining the body and preventing it from being thrown forward. When a collision occurs, the body tends to continue moving at the same speed and direction as the vehicle before the impact. By wearing a seatbelt, the body is held back, reducing the force and momentum exerted on it. This helps to prevent or minimize injuries by preventing the body from hitting hard surfaces inside the vehicle or being ejected from the vehicle.
12.
When objects collide, some momentum is lost
Correct Answer
B. False
Explanation
When objects collide, momentum is conserved according to the law of conservation of momentum. This means that the total momentum before the collision is equal to the total momentum after the collision. So, no momentum is lost in a collision. Therefore, the statement "When objects collide, some momentum is lost" is false.
13.
When an object speeds up, it increases it's momentum
Correct Answer
A. True
Explanation
When an object speeds up, it increases its momentum because momentum is directly proportional to the velocity of an object. As velocity increases, momentum also increases. This is because momentum is defined as the product of an object's mass and its velocity. Therefore, when an object speeds up, its momentum increases.
14.
Momentum can be transferred from one object to another
Correct Answer
A. True
Explanation
Momentum is a fundamental concept in physics that describes the quantity of motion an object possesses. According to the principle of conservation of momentum, momentum can be transferred from one object to another in a closed system. This transfer can occur through various mechanisms such as collisions or interactions between objects. Therefore, the statement "Momentum can be transferred from one object to another" is true.
15.
Objects with different masses can't have the same momentum.
Correct Answer
B. False
Explanation
This statement is false because momentum is a vector quantity that depends on both mass and velocity. Two objects with different masses can have the same momentum if their velocities are adjusted accordingly. The momentum of an object is given by the product of its mass and velocity, so as long as the product of mass and velocity is the same for two objects, their momentum will be equal.
16.
Direction does not matter when you are measuring momentum.
Correct Answer
B. False
Explanation
The statement is false because the direction does matter when measuring momentum. Momentum is a vector quantity, which means it has both magnitude and direction. In physics, momentum is calculated by multiplying an object's mass by its velocity. The direction of an object's velocity affects its momentum, as momentum is dependent on both speed and direction. Therefore, when measuring momentum, it is important to consider the direction of the object's motion.