asked 159k views
1 vote
A body of mass 100 kg falls from a height of 10 m. Its increase in kinetic energy is​-----------

1 Answer

4 votes

Step-by-step explanation:

The increase in kinetic energy of a body when it falls from a height can be calculated using the following formula:

\[ \text{Increase in Kinetic Energy} = \text{Final Kinetic Energy} - \text{Initial Kinetic Energy} \]

The initial kinetic energy (\(KE_{\text{initial}}\)) of the body is zero because it's initially at rest. The final kinetic energy (\(KE_{\text{final}}\)) can be calculated using the formula:

\[ KE_{\text{final}} = \frac{1}{2} \cdot m \cdot v^2 \]

Where:

- \( m \) is the mass of the body (100 kg).

- \( v \) is the final velocity of the body when it hits the ground.

To find \( v \), you can use the following kinematic equation:

\[ v^2 = u^2 + 2as \]

Where:

- \( u \) is the initial velocity (which is 0 m/s because the body starts from rest).

- \( a \) is the acceleration due to gravity (approximately 9.81 m/s², assuming standard Earth gravity).

- \( s \) is the height from which the body falls (10 m).

Plugging in the values:

\[ v^2 = 0^2 + 2 \cdot 9.81 \cdot 10 \]

\[ v^2 = 196.2 \]

\[ v ≈ 14.0 \, \text{m/s} \]

Now, calculate the final kinetic energy:

\[ KE_{\text{final}} = \frac{1}{2} \cdot 100 \, \text{kg} \cdot (14.0 \, \text{m/s})^2 \]

\[ KE_{\text{final}} ≈ 9800 \, \text{Joules} \]

Now, calculate the increase in kinetic energy:

\[ \text{Increase in Kinetic Energy} = KE_{\text{final}} - KE_{\text{initial}} = 9800 \, \text{Joules} - 0 \, \text{Joules} \]

So, the increase in kinetic energy of the body is 9800 Joules.

answered
User Maxkonovalov
by
8.9k points

No related questions found

Welcome to Qamnty — a place to ask, share, and grow together. Join our community and get real answers from real people.