The rate of change of ___ is called acceleration.

Selena is classifying different moving objects into two categories, i.e., rotational motion and periodic motion. She has the following motions to classify:
a. The motion of a swing
b. The motion of the Earth around the Sun
c. The motion of a giant wheel
d. The motion of the blades of a fan at a particular speed
e. The motion of the hands of a clock
f. The motion of a roller coaster
g. The motion of a merry-go-round
h. The motion of a pendulum
She could identify some of the above objects, which can be put in both categories. What are those?

A man is driving a car at a constant speed. What is the state of the man w.r.t. a person sitting inside the car?

A man is driving a car at a constant speed. What is the state of the man w.r.t. a tree on the road?

Pick the odd one out.

In a bowling game, what type of motion does the ball perform in the lane? What type of motion do the pins perform when hit by the ball?

Taking the traffic pole as a reference point, Sam observed the state of the passenger inside the yellow bus. He found that the passenger was in motion w.r.t. the traffic pole. What is the frame of reference in which this observation is made?

Which of the following motions repeat themselves after equal intervals of time?

1. The motion of the Moon around the Earth
2. The motion of the hour hand of a clock
3. The motion of a tennis ball during a match
4. The motion of a seesaw when children are playing

the motion of the moon around the earth and the motion of the hour hand of the clock is a periodic motion hence, they repeat themselves after equal intervals of time.

An object moves in such a way that it always stays at a fixed distance from a fixed point. Identify the type of motion of the body

Pick the odd one out.

.

Which of the following is not an example of rectilinear motion?

Peter collects objects which perform a periodic motion as part of project work. He has already included a pendulum, the guitar, and a toy swing in his collection. Should he also include a wristwatch? Give reasons

Samuel decides to find the average speed of his parent’s car while they take a drive to a park 21 km away from their home. Which of the following would yield him the most accurate result?
a. Look for milestones throughout the journey and note down the distance traveled against the respective time stamps. Later use the formula, average speed = total distance traveled / total time taken to calculate the average speed.
b. Keep an eye on the odometer and note down the distance traveled by car against the respective time stamps. Later use the formula, average speed = total distance traveled / total time taken to calculate the average speed.
c. Keep an eye on the speedometer and note down the speed at different locations. Later use the formula average speed = sum of all the speeds/ no. of observations to calculate the average

Observe the picture below. Can we consider the position of the child as a reference point to study the state of a person sitting inside the car? Give reasons