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a 10g bullet moving at 70ms-2 penetrates a block of wood 5cm before stopping. determine the kinetic energy of the bullet

User Phyzalis
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Final answer:

The kinetic energy of a 10g bullet moving at 70 m/s is calculated to be 24.5 Joules using the kinetic energy formula KE = \( \frac{1}{2}mv^2 \).

Step-by-step explanation:

To determine the kinetic energy of a bullet, we can use the formula for kinetic energy which is KE = \( \frac{1}{2}mv^2 \), where m is the mass of the bullet and v is its velocity. In this case, the mass of the bullet is 10 g (which is 0.01 kg when converted to kilograms) and its velocity is 70 m/s. Therefore, the calculation will be:

KE = \( \frac{1}{2} \times 0.01 \text{kg} \times (70 \text{m/s})^2 \)

KE = \( \frac{1}{2} \times 0.01 \times 4900 \)

KE = \( 0.005 \times 4900 \)

KE = 24.5 J

So, the kinetic energy of the bullet before it stops is 24.5 Joules.

To determine the kinetic energy of the bullet, we can use the equation:

KE = ½mv^2

where KE is the kinetic energy, m is the mass of the bullet, and v is the velocity of the bullet.

Given that the mass of the bullet is 10g (0.01kg) and the velocity is 70m/s, we can substitute these values into the equation:

KE = ½ · 0.01kg · (70m/s)^2

Calculating this expression, we get:

KE = 0.005kg · 4900m^2/s^2 = 24.5J

Therefore, the kinetic energy of the bullet is 24.5J.

User Mckoss
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