Physics

Kinematics and Dynamics of Motion

121 Questions

Kinematics and dynamics explore projectile motion, inertia, free fall, and kinetic energy. These physics topics frequently appear in general science papers of major competitive exams. Practice these questions to understand the mechanical laws of motion.

Projectile motionFree fall calculationsInertia conceptsKinetic energyImpulse and collision

Kinematics and Dynamics of Motion Questions

Multiple choice general knowledge math & puzzles

A ball is dropped from a height of 120 m, and bounces back to 5/6 of previous height every time. Calculate total distance travelled by the ball till it becomes stationary..

  1. 1340 m

  2. 1360 m

  3. 1320 m

  4. 1380 m
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The ball drops 120 m down, then bounces back up to 100 m (5/6 of 120), down again 100 m, up to 83.33 m (5/6 of 100), continuing this geometric pattern. Total distance = 120 + 2×100 + 2×83.33 + 2×69.44 + ... = 120 + 2×120(5/6 + 25/36 + 125/216 + ...) = 120 + 2×120 × (5/6)/(1-5/6) = 120 + 2×120×5 = 1320 m.

Multiple choice general knowledge math & puzzles

In the comic’s nakshatra, I.G rajan is hanging by a rope tied to his waist and is unconscious. He is hanging at top of the building which is 100 meter high. The height of I.G rajan is 1.75 meters. Dhruv has to save him. Dhruv is 30 meter away from the base of building and is in perfect straight line with fall of I.G rajan. Dhruv notices a cart of sand that can break I.G rajan fall and thus can in turn save him. How much time Dhruv has in total to react? Take G=9.825 unit

  1. 5 sec

  2. 4.4 sec

  3. 3 sec

  4. 2 sec
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

For free fall from height h: h = ½gt². With h = 100m and g = 9.825 m/s²: t = √(2h/g) = √(200/9.825) = √20.36 ≈ 4.51 seconds. Option B (4.4s) is the closest approximation - the slight difference comes from rounding in intermediate steps.

Multiple choice general knowledge science & technology

Consider the following scenario : 'A cat accidentally drops from the seventh floor of a high rise. It does not face any casualty, infact it is perfectly alright, because of it's well padded paws. But the same cat fell down from the third floor some days later and suffered a few bruises.' Please select the correct reason from the below options : [Hint:- Try fluid mechanics]

  1. There was too much wind the second day for the cat to settle down

  2. The cat was fatigued out due to repetitve accidents

  3. The cat tried a different way of landing and failed

  4. The air friction in the first case helped the cat
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The cat survives falls from higher floors because air resistance (drag) increases with speed, leading to a terminal velocity. From the seventh floor, the cat reaches terminal velocity and can orient itself to land properly. From the third floor, it hasn't reached terminal velocity and has less time to right itself.

Multiple choice general knowledge science & technology

If a rock is thrown straight up with an initial velocity of 30 meters per second, the rock will reach a height of approximately ...

  1. 90 m

  2. 45 m

  3. 30 m

  4. 60 m
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

At maximum height, the rock's final velocity is zero. Using the kinematic equation v² = u² + 2as where v = 0, u = 30 m/s, and a = -9.8 m/s² (downward), we solve for height: 0 = 30² + 2(-9.8)h, giving h = 900/19.6 ≈ 45.9 meters, which rounds to approximately 45 meters.

Multiple choice general knowledge

If I were in Hawaii and dropped a bowling ball in a bucket of water which is 45 degrees F, and dropped another ball of the same weight, mass, and size in a bucket at 30 degrees F, both of them at the same time, which ball would hit the bottom of the bucket first? Same question, but the location is in Canada?

  1. ball in the bucket of 45 degree F

  2. ball in the bucket of 30 degree F

  3. ball in the bucket of 90 degree F

  4. ball in the bucket of 60 degree F
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Both balls are the same weight, mass, and size. Gravity accelerates all objects equally regardless of temperature. The ball in the warmer water (45°F) would hit bottom first because liquid water exists at 45°F, but at 30°F water would be frozen (ice), so the second ball wouldn't fall through at all. In Canada (colder climate), the 30°F bucket would be frozen solid.

Multiple choice general knowledge culture

Balls usually consist of several layers of various synthetic materials like surlyn or urethane blends. Weighs no more than 1.62 oz (45.93 grams), has a diameter not less than 1.68 in (42.67 mm), and performs within specified velocity, distance, and symmetry limits. Has numerous dimples (250 – 450) all over its body. Use clue if u cannot get it still.

  1. Baseball Ball

  2. Polo Ball

  3. Tennis Ball

  4. Golf ball
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A golf ball is uniquely identified by: maximum 1.62 oz weight, minimum 1.68 inch diameter, multiple layers (surlyn/urethane), and 250-450 dimples covering its surface. No other ball has dimples or matches these specs.

Multiple choice general knowledge science & technology

A BODY IS THROWN FROM A 40 METER HIGH BUILDING TOWARDS GROUND AT A VELOCITY OF 10m/s.IF g = 10 m/s-s THEN FIND VELOCITY OF BALL WHEN IT STRIKES GROUND.

  1. 50 m/s

  2. 40 m/s

  3. 0 m/s

  4. 30 m/s
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Using the kinematic equation v² = u² + 2as, where initial velocity u = 10 m/s (downward), acceleration a = g = 10 m/s², and displacement s = 40 m. This gives v² = 100 + 2(10)(40) = 900, so v = 30 m/s. Options A and B incorrectly ignore initial velocity or miscalculate, while C is physically meaningless.

Multiple choice general knowledge science & technology

maximum height reached by a stone thrown upwards is SquareOf(u)/2*g; where u =Initial velocity g=gravity.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The maximum height (H) reached by a projectile thrown vertically upward with initial velocity u is given by H = u²/(2g), where g is acceleration due to gravity. This formula is derived from the kinematic equation v² = u² - 2gH, setting final velocity v = 0 at the maximum height. The formula given in the question (SquareOf(u)/2*g) correctly represents this relationship.

Multiple choice general knowledge science & technology

Ben travels to a distant planet. In outerspace, with essentially no gravity, he can throw a baseball (mass = 0.5 kg) and a shot put (mass = 4 kg) at the same speed with no discernable difference in effort.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Even without gravity, accelerating a more massive object requires more force (F=ma). To throw both at the same speed, you must exert greater force on the 4kg shot put than the 0.5kg baseball.

Multiple choice general knowledge science & technology

If you release a ball inside a freely-falling elevator it stays in front of you instead of "falling to the floor" because you, the ball, and the elevator are all accelerating downward at the same acceleration, g. If you similarly release a helium-filled balloon, the balloon will--

  1. press against the ceiling

  2. press against the floor

  3. squeeze and blast due to non-uniform air pressure

  4. also stay in front of you
Reveal answer Fill a bubble to check yourself
D Correct answer
Multiple choice

A person sitting in an open car moving at constant velocity throws a ball vertically upwards in air. If effect of air resistance is neglected, the ball-will fall-

  1. Exactly in the hands of the person

  2. Outside the car

  3. In the car behind the person

  4. In the car ahead of the person
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

When the ball is thrown vertically upward in a car moving at constant velocity, it retains the horizontal velocity of the car (Galilean relativity). The ball and the thrower continue moving forward together at the same speed, so the ball falls back into the thrower's hands. Air resistance would change this outcome, but the problem states it's neglected. This is the same principle that allows passengers to toss objects in a moving train or airplane.