A body of mass 1000 kg is moving horizontally with a velocity of 6 m/s. If 200 kg extra mass is added, the final velocity (in m/s) is:
A body of mass 1000 kg is moving horizontally with a velocity of 6 m/s. If 200 kg extra mass is added, the final velocity (in m/s) is:
- 5 m/s
- 4 m/s
- 2 m/s
- 6 m/s
The Correct Option is A
Solution and Explanation
Since there are no external forces, momentum is conserved. Initially:
\[ \text{Initial momentum} = 1000 \times 6 = 6000 \, \text{kg m/s} \]
After adding 200 kg of mass, the total mass becomes 1200 kg. Let the final velocity be \(v\).
Using conservation of momentum:
\[ 1200 \times v = 6000 \] \[ v = \frac{6000}{1200} = 5 \, \text{m/s} \]
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Concepts Used:
Speed and Velocity
The rate at which an object covers a certain distance is commonly known as speed.
The rate at which an object changes position in a certain direction is called velocity.
Difference Between Speed and Velocity:
Read More: Difference Between Speed and Velocity