A bullet of mass 0.01 kg and travelling at a speed of500 m/s strikes a...
Suppose v1 and v2 are the velocities of the bullet and the block after collision.Since the block rises to a height h=0.01 m, so all its kinetic energy is converted into its potential energy.Thus, by conservation of energy,
If u1 is the initial velocity of the bullet, then applying the law of conservation of momentum along the initial direction of the bullet,
We get
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A bullet of mass 0.01 kg and travelling at a speed of500 m/s strikes a...
Given data:
Mass of bullet (m1) = 0.01 kg
Initial velocity of bullet (u1) = 500 m/s
Mass of block (m2) = 2 kg
Length of string (L) = 5 m
Vertical distance block rises (h) = 0.1 m
Using the principle of conservation of momentum, we can calculate the velocity of the bullet after it emerges from the block.
1. Calculate the initial momentum of the bullet before it hits the block:
Initial momentum of bullet (p1) = mass of bullet × initial velocity = m1 × u1
2. Calculate the final momentum of the bullet after it emerges from the block:
Final momentum of bullet (p2) = mass of bullet × final velocity (v2)
3. Calculate the momentum of the block after the impact:
Momentum of block (p3) = mass of block × final velocity (v3)
4. Apply the principle of conservation of momentum:
According to the principle of conservation of momentum, the total momentum before the impact is equal to the total momentum after the impact.
Initial momentum = Final momentum
(p1) = (p2) + (p3)
5. Substitute the values into the equation:
m1 × u1 = m1 × v2 + m2 × v3
6. Solve for v2, the final velocity of the bullet after it emerges from the block:
v2 = (m1 × u1 - m2 × v3) / m1
7. Calculate the final velocity of the block:
The final velocity of the block (v3) can be calculated using the concept of conservation of energy.
The potential energy gained by the block is equal to the gravitational potential energy lost by the bullet-block system.
Potential energy gained by the block = m2 × g × h
Gravitational potential energy lost by the bullet-block system = m1 × g × h
where g is the acceleration due to gravity.
8. Calculate the value of v3:
m2 × v3 = m1 × g × h
v3 = (m1 × g × h) / m2
9. Substitute the value of v3 into the equation for v2:
v2 = (m1 × u1 - m2 × (m1 × g × h) / m2) / m1
Simplifying, we get:
v2 = (m1 × u1 - m1 × g × h)
10. Substitute the given values into the equation:
v2 = (0.01 kg × 500 m/s - 0.01 kg × 9.8 m/s^2 × 0.1 m) / 0.01 kg
v2 = (5 - 0.098) m/s
v2 = 4.902 m/s
Therefore, the speed of the bullet after it emerges from the block is approximately 4.902 m/s, which can be rounded off to 5 m/s.
The correct answer is option B, 220 m/s.