An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass $1\, kg$ moves with a speed of $12 \, ms^{-1}$ and the second part of mass $2 \,kg$ moves with $8 \, ms^{-1}$ speed. If the third part files off with $4 \, ms^{-1}$ speed, then its mass is :
- 17 kg
- 3 kg
- 5 kg
- 7 kg
The Correct Option is C
Solution and Explanation
$ m(4) = \sqrt{ (1 \times 12)^2 + (2 \times 8)^2} \Rightarrow m = 5 kg $
Top Questions on laws of motion
- A force of \( 10 \, \text{N} \) acts on a body of mass \( 2 \, \text{kg} \). What is the acceleration of the body?
- VITEEE - 2025
- Physics
- laws of motion
- A body of mass 5 kg is moving with a velocity of 15 m/s. What is its momentum?
- VITEEE - 2025
- Physics
- laws of motion
- A car of mass 1000 kg is moving with a velocity of 20 m/s. The driver applies the brakes, and the car comes to rest in 10 seconds. Find the average force exerted by the brakes to stop the car.
- MHT CET - 2025
- Physics
- laws of motion
- A ball is thrown vertically upwards with an initial velocity of 20 m/s. If the acceleration due to gravity is \( 10 \, \text{m/s}^2 \), what is the maximum height reached by the ball?
- MHT CET - 2025
- Physics
- laws of motion
- A 2 kg object is hanging vertically from a rope. The tension in the rope is 15 N. What is the acceleration of the object? (Assume \( g = 9.8 \, \text{m/s}^2 \))
- MHT CET - 2025
- Physics
- laws of motion
Questions Asked in NEET exam
- A thin flat circular disc of radius 4.5 cm is placed gently over the surface of water. If surface tension of water is 0.07 Nm-1, then the excess force required to take it away from the surface is :
- NEET (UG) - 2024
- Surface tension
- Arrange the following elements in increasing order of first ionization enthalpy:
Li, Be, B, C, N
Choose the correct answer from the options given below:- NEET (UG) - 2024
- Enthalpy change
In a Vernier caliper, \(N+1\) divisions of vernier scale coincide with \(N\) divisions of main scale. If 1 MSD represents 0.1 mm, the vernier constant (in cm) is:
- NEET (UG) - 2024
- Units, Dimensions and Measurements
- In an ecosystem if the Net Primary Productivity (NPP) of first trophic level is 100x (kcal m-2)yr-1, what would be the GPP (Gross Primary Productivity) of the third trophic level of the same ecosystem?
- NEET (UG) - 2024
- Ecosystems
- Two bodies A and B of same mass undergo completely inelastic one dimensional collision. The body A moves with velocity v1 while body B is at rest before collision. The velocity of the system after collision is v2. The ratio v1 : v2 is :
- NEET (UG) - 2024
- Average Velocity and Instantaneous Velocity
Concepts Used:
Laws of Motion
The laws of motion, which are the keystone of classical mechanics, are three statements that defined the relationships between the forces acting on a body and its motion. They were first disclosed by English physicist and mathematician Isaac Newton.
Newton’s First Law of Motion
Newton’s 1st law states that a body at rest or uniform motion will continue to be at rest or uniform motion until and unless a net external force acts on it.
Newton’s Second Law of Motion
Newton's 2nd law of motion deals with the relation between force and acceleration. According to the second law of motion, the acceleration of an object as built by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
Newton’s Third Law of Motion
Newton's 3rd law of motion states when a body applies a force on another body that there is an equal and opposite reaction for every action.