Physics Multiple Choice Questions on “Motion in a Plane”.
1. How many variables are required to define the motion of a body in a plane?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: The motion of a body in a plane can be defined by using two variables. These are the two defining axes of the Coordinate system, x and y. Once we have the displacement as a function of these to variables, any other quantity can be found out.
2. A body is exhibiting circular motion. What kind of motion can this be termed as?
a) Motion along a line
b) Motion in a plane
c) Motion in space
d) Motion along a point
Answer: b
Clarification: Circular motion is an example of motion in a plane. As a circle is a 2-dimensional entity, the body moving in a circle is also moving in a plane. Hence the motion can be termed as motion in a plane.
3. Which of the following is not an example of motion in a plane?
a) A car moving in a rectangular path
b) A bicycle moving in a circular path
c) A rocket moving into space
d) A truck moving in an infinite spiral
Answer: c
Clarification: A rocket moving into space is an example of 3-dimensional motion. Hence, it cannot be out in the category of motion in a plane. Rest all examples of motion in a plane. The truck moving in an infinite spiral is also an example of motion in a plane as spiral is a 2-dimensional entity.
4. In how many independent directions can a vector in a plane be resolved?
a) 1
b) 2
c) 3
d) 4
Answer: b
Clarification: A vector in a plane will be defined by the two governing axes, X and Y. Hence, any vector can be resolved in two independent directions. If it is resolved in any other direction, that component of it will be dependent on the existing independent directions.
5. Which of the following is not true about projectile motion?
a) It is an example of motion in a plane
b) It is an example of motion along a curve
c) It is not an example of motion in space
d) The acceleration keeps changing in projectile motion
Answer: a
Clarification: The only acceleration in projectile motion is the acceleration due to gravity. If the maximum height of the projectile motion is not large, and can be neglected with respect to the radius of earth (which usually is the case), the acceleration due to gravity remains constant. Hence, the acceleration in projectile motion remains constant.