JEE (Main) Physics - Motion in a Plane, Projectile Motion, Uniform Circular Motion MCQs

61. What is the angle between the velocity vector and acceleration vector in uniform circular motion?

• A) 0°
• B) 90°
• C) 45°
• D) 180°

Answer: B) 90°

62. In projectile motion, the horizontal velocity remains constant because:

• A) There is no force acting horizontally.
• B) There is no vertical component in the motion.
• C) Air resistance is neglected.
• D) The vertical velocity is zero.

Answer: C) Air resistance is neglected.

63. In a uniform circular motion, the direction of the velocity vector is:

• A) Along the radius of the circle.
• B) Tangential to the circle.
• C) Radially outward from the center.
• D) Radially inward towards the center.

Answer: B) Tangential to the circle.

64. The range of a projectile is maximum when the angle of projection is:

• A) 30°
• B) 45°
• C) 60°
• D) 90°

Answer: B) 45°

65. A particle moves in a circle of radius 5 m with a constant speed of 10 m/s. What is the magnitude of its acceleration?

• A) 5 m/s²
• B) 10 m/s²
• C) 20 m/s²
• D) 50 m/s²

Answer: B) 10 m/s²

66. For an object in projectile motion, the time of flight depends on:

• A) Initial velocity
• B) Angle of projection
• C) Both initial velocity and angle of projection
• D) Acceleration due to gravity

Answer: C) Both initial velocity and angle of projection

67. A body is thrown vertically upwards. What is the velocity of the body at the maximum height?

• A) Maximum
• B) Zero
• C) Infinity
• D) Minimum

Answer: B) Zero

68. Which of the following equations is used to calculate the centripetal acceleration of an object moving in uniform circular motion?

• A) \(a_c = \frac{v^2}{r}\)
• B) \(a_c = \frac{r^2}{v}\)
• C) \(a_c = \frac{r}{v^2}\)
• D) \(a_c = v \cdot r\)

Answer: A) \(a_c = \frac{v^2}{r}\)

69. In projectile motion, the vertical component of velocity is:

• A) Constant
• B) Increasing
• C) Decreasing
• D) Zero

Answer: C) Decreasing

70. Which of the following is true for an object in uniform circular motion?

• A) It moves in a straight line.
• B) It experiences no force.
• C) The velocity is constant in magnitude but changes in direction.
• D) The speed changes with time.

Answer: C) The velocity is constant in magnitude but changes in direction.

71. In a projectile motion, the time taken to reach the maximum height is:

• A) Half the total time of flight
• B) Equal to the total time of flight
• C) One-fourth of the total time of flight
• D) Zero

Answer: A) Half the total time of flight

72. The velocity of an object moving in uniform circular motion is always:

• A) Tangential to the circle
• B) Radial inward
• C) Radial outward
• D) Constant in direction and magnitude

Answer: A) Tangential to the circle

73. If the angle of projection of a projectile is increased from 30° to 45°, the range of the projectile will:

• A) Increase
• B) Decrease
• C) Remain the same
• D) First increase, then decrease

Answer: A) Increase

74. The acceleration of a body moving in a circle is directed:

• A) Tangential to the circle
• B) Away from the center of the circle
• C) Toward the center of the circle
• D) Perpendicular to the plane of motion

Answer: C) Toward the center of the circle

75. For an object to perform uniform circular motion, the net force acting on the object must be:

• A) Zero
• B) Constant in magnitude and direction
• C) Radial and directed towards the center
• D) Tangential to the circle

Answer: C) Radial and directed towards the center