1.
A push or a pull is called
Correct Answer
B. Force
Explanation
Force is the correct answer because a push or a pull is defined as a force. Force is a physical quantity that can cause an object to accelerate, change its shape, or deform. It is a vector quantity, which means it has both magnitude and direction. In this context, a push or a pull can be considered as a force acting on an object, resulting in motion or a change in motion.
2.
James combines all the forces acting on a tennis ball. He is finding.....
Correct Answer
A. Net force
Explanation
James is finding the net force acting on a tennis ball. The net force is the vector sum of all the individual forces acting on an object. It determines the overall acceleration or deceleration of the object. By combining all the forces, James can determine the net force and understand how it affects the motion of the tennis ball.
3.
Janet is sliding a box across the floor. What does she need to know to calculate the force on the box?(F=ma)
Correct Answer
C. Mass and acceleration
Explanation
To calculate the force on the box, Janet needs to know the mass of the box and the acceleration it is experiencing. The force is directly proportional to the mass and acceleration of an object, as stated by Newton's second law of motion (F=ma). Therefore, knowing both the mass and acceleration of the box will allow Janet to calculate the force exerted on it.
4.
Inertia is the resistance of an object to a change in its
Correct Answer
B. Motion
Explanation
Inertia refers to the resistance of an object to a change in its motion. It is a property of matter that causes objects to resist any change in their state of motion. This means that an object at rest tends to stay at rest, and an object in motion tends to stay in motion with the same speed and direction, unless acted upon by an external force. Therefore, motion is the correct answer as it accurately describes the concept of inertia.
5.
A soccer player kicks a ball that is at rest. What do you predict will happen?
Correct Answer
D. The ball will accelerate in the same direction as the applied force
Explanation
When a soccer player kicks a ball that is at rest, the ball will accelerate in the same direction as the applied force. This is because Newton's second law of motion states that an object will accelerate in the direction of the net force acting on it. In this case, the applied force from the player's kick will cause the ball to accelerate in the same direction as the force, causing it to move forward.
6.
According to Newton's second law of motion, force equals mass times ......
Correct Answer
C. Acceleration
Explanation
According to Newton's second law of motion, force equals mass times acceleration. This law states that the force acting on an object is directly proportional to the mass of the object and the acceleration it experiences. Therefore, the correct answer is acceleration.
7.
When you push on a door, the door pushes back with an equal and opposite force. These two forces are known as
Correct Answer
D. Action/reaction force pairs
Explanation
When you push on a door, the door pushes back with an equal and opposite force. This is known as an action/reaction force pair. According to Newton's third law of motion, for every action, there is an equal and opposite reaction. In this case, the action is the force exerted by you on the door, and the reaction is the force exerted by the door back on you. These forces always occur in pairs and act on different objects.
8.
The momentum of an object is the product of its(p=mv)
Correct Answer
B. Mass and velocity
Explanation
The momentum of an object is defined as the product of its mass and velocity. This is derived from the equation p=mv, where p represents momentum, m represents mass, and v represents velocity. The mass of an object refers to the amount of matter it contains, while velocity refers to the speed and direction of its motion. Therefore, the correct answer is mass and velocity.
9.
A bowling ball rolls down the lane and hits some pins before rolling off the lane. What happens to the momentum of the ball as it hits the pins?
Correct Answer
A. Some of the ball's momentum is transferred to the pins
Explanation
When the bowling ball hits the pins, some of its momentum is transferred to the pins. This is because momentum is conserved in a collision. The collision between the ball and the pins causes a transfer of momentum from the ball to the pins. However, not all of the ball's momentum is transferred, as some of it is also retained by the ball, causing it to continue rolling off the lane.
10.
Conservation of momentum occurs only when there are........
Correct Answer
A. No outside forces
Explanation
Conservation of momentum occurs only when there are no outside forces acting on the system. This means that the total momentum of the system remains constant, regardless of any internal forces or interactions between objects within the system. In the absence of external forces, the momentum of the system before an event or interaction will be equal to the momentum of the system after the event or interaction. This principle is a fundamental concept in physics and is applicable in various scenarios, such as collisions or explosions.
11.
What is the unit of force?
Correct Answer
C. Newton
Explanation
The unit of force is the newton. The newton is the standard unit of force in the International System of Units (SI). It is defined as the force required to accelerate a one-kilogram mass by one meter per second squared. The newton is named after Sir Isaac Newton, who made significant contributions to the field of physics and mechanics.
12.
What symbol is used for force?
Correct Answer
A. N
Explanation
The symbol used for force is N, which stands for Newton. Newton is the unit of force in the International System of Units (SI). It is named after Sir Isaac Newton, a renowned physicist who made significant contributions to the field of mechanics and formulated the laws of motion. The symbol N is widely used in physics and engineering to represent force in equations and calculations.
13.
What is one of the forces involved in pushing the cart?
Correct Answer
B. Contact force in pushing
Explanation
The correct answer is contact force in pushing because when we push a cart, we exert a force on it through direct contact. This force allows us to overcome the inertia of the cart and move it in the desired direction. Gravitational force pushing up is not relevant in this context as it acts vertically to counteract the force of gravity. Inertia force is not a recognized force, and energy force is not a valid term in physics.
14.
What force is being applied to the cart of it is accelerating at 2.2 m/s2 and the cart's mass is 55 kg? The formula for calculating force is F=ma
Correct Answer
D. 121N
Explanation
According to the formula for calculating force (F = ma), the force applied to an object is equal to its mass multiplied by its acceleration. In this case, the cart has a mass of 55 kg and is accelerating at 2.2 m/s^2. Therefore, the force being applied to the cart can be calculated as F = 55 kg * 2.2 m/s^2 = 121 N.
15.
If you double the force on the cart, what happens to the acceleration?
Correct Answer
A. It doubles as well
Explanation
When you double the force on the cart, according to Newton's second law of motion, the acceleration of an object is directly proportional to the force applied to it. Therefore, if the force is doubled, the acceleration will also double.
16.
What do the data show about momentum as the mass becomes larger? CarabcdefgMass of car (kg)1350140014501500155016001650Momentum (kg m/s)2970308031903300341035203630
Correct Answer
D. Momentum increases as mass becomes larger
Explanation
As the mass becomes larger, the momentum also increases. This can be observed from the given data where the momentum values increase as the mass of the car increases. Therefore, the correct answer is that momentum increases as mass becomes larger.
17.
Use the data in the table to determine the velocity of car A. The formula for calculating velocity is V=P/m (velocity = momentum/mass) carabcdefgmass of car (kg)1350140014501500155016001650momentum (kg m/s)2970308031903300341035203630
Correct Answer
B. 2.2 m/s
Explanation
The formula for calculating velocity is V = P/m, where V is velocity, P is momentum, and m is mass. Looking at the table, the momentum of car A is given as 3080 kg m/s and the mass is given as 1400 kg. Plugging these values into the formula, we get V = 3080/1400 = 2.2 m/s. Therefore, the velocity of car A is 2.2 m/s.