1.
Which of these cannot be considered as acceleration?
Correct Answer
A. Moving at the same velocity on a straight line
Explanation
Moving at the same velocity on a straight line cannot be considered as acceleration because acceleration is defined as the rate of change of velocity. When an object moves at a constant velocity on a straight line, there is no change in its velocity, hence no acceleration. Acceleration only occurs when there is a change in speed, direction, or both.
2.
What is a negative acceleration called?
Correct Answer
C. Deceleration
Explanation
Deceleration refers to the decrease in velocity or speed of an object over time. It is commonly known as negative acceleration because it represents a change in velocity that is opposite to the direction of motion. When an object decelerates, it slows down, resulting in a negative value for acceleration. This term is used to describe situations where an object is slowing down or coming to a stop.
3.
Which of these is the dimension for acceleration?
Correct Answer
D. L/T²
Explanation
The dimension for acceleration is L/T², which represents length divided by time squared. This is because acceleration is defined as the rate of change of velocity with respect to time. Velocity has the dimension L/T, representing length divided by time. Taking the derivative of velocity with respect to time gives us the dimension L/T², representing length divided by time squared, which is the dimension for acceleration.
4.
The average acceleration of an object over a period of time is termed which of these?
Correct Answer
C. Change in velocity
Explanation
The average acceleration of an object over a period of time is determined by the change in velocity. Acceleration measures how quickly an object's velocity changes, so the average acceleration can be calculated by dividing the change in velocity by the time taken. Therefore, "Change in velocity" is the correct term to describe the average acceleration of an object.
5.
Which of these is a vector quantity?
Correct Answer
D. Displacement
Explanation
Displacement is a vector quantity because it has both magnitude and direction. It refers to the change in position of an object from its initial to final position, taking into account the shortest path between the two points. In contrast, speed, distance, and mass are scalar quantities as they only have magnitude and no direction associated with them.
6.
Why is speed considered to be a scaler quantity?
Correct Answer
C. It has magnitude but no direction
Explanation
Speed is considered to be a scalar quantity because it only has magnitude and no direction. Scalar quantities are described solely by their magnitude, such as distance, temperature, or mass. In the case of speed, it represents the magnitude of the rate at which an object is moving, but it does not indicate the direction of motion. Therefore, speed is a scalar quantity.
7.
What is the term given to the limit of the average acceleration over an infinitesimal interval of time?
Correct Answer
C. Instantaneous acceleration
Explanation
The term given to the limit of the average acceleration over an infinitesimal interval of time is instantaneous acceleration. This refers to the acceleration of an object at a specific moment in time, rather than an average over a longer period. It represents the rate at which an object's velocity is changing at that particular instant.
8.
Cheryl traveled a total distance of 440 miles. Her trip took 8 hours. What was her average speed?
Correct Answer
A. 55
Explanation
Cheryl's average speed can be calculated by dividing the total distance traveled (440 miles) by the time taken (8 hours). Therefore, her average speed is 55 miles per hour.
9.
What is the area of the curve under an Acceleration-Time graph?
Correct Answer
C. Velocity
Explanation
The area under an Acceleration-Time graph represents the change in velocity. Velocity is the rate at which an object changes its position with respect to time. Therefore, the correct answer is velocity.
10.
What is the SI unit of acceleration?
Correct Answer
B. M/s²
Explanation
The SI unit of acceleration is m/s², which stands for meters per second squared. This unit represents the change in velocity per unit of time, indicating how quickly an object's velocity is changing. In this case, the unit m/s² means that for every second, the velocity of the object is increasing or decreasing by a certain number of meters per second.