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Given that the displacement of the body ...

Given that the displacement of the body in metre is a function of time as follows
`x=2t^(4)+5`
The mass of the body is 2 kg. What is the increase in its kinetic energy one second after the start of motion?

A

8 J

B

16 J

C

32 J

D

64 J

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem step by step, we need to find the increase in kinetic energy of the body one second after the start of motion. ### Step 1: Identify the displacement function The displacement of the body is given by the equation: \[ x = 2t^4 + 5 \] ### Step 2: Find the velocity function To find the velocity, we need to differentiate the displacement function with respect to time \( t \): \[ v = \frac{dx}{dt} = \frac{d}{dt}(2t^4 + 5) \] Using the power rule of differentiation: \[ v = 8t^3 \] ### Step 3: Calculate the velocity at \( t = 1 \) second Now, we will calculate the velocity at \( t = 1 \) second: \[ v(1) = 8(1)^3 = 8 \, \text{m/s} \] ### Step 4: Calculate the initial velocity at \( t = 0 \) seconds Next, we will find the initial velocity at \( t = 0 \): \[ v(0) = 8(0)^3 = 0 \, \text{m/s} \] ### Step 5: Calculate the increase in kinetic energy The kinetic energy \( K \) is given by the formula: \[ K = \frac{1}{2}mv^2 \] The increase in kinetic energy \( \Delta K \) from \( t = 0 \) to \( t = 1 \) second is: \[ \Delta K = K(1) - K(0) \] Where: - \( K(1) = \frac{1}{2} m v(1)^2 \) - \( K(0) = \frac{1}{2} m v(0)^2 \) Substituting the values: - Mass \( m = 2 \, \text{kg} \) - \( v(1) = 8 \, \text{m/s} \) - \( v(0) = 0 \, \text{m/s} \) Calculating \( K(1) \): \[ K(1) = \frac{1}{2} \times 2 \times (8)^2 = 1 \times 64 = 64 \, \text{J} \] Calculating \( K(0) \): \[ K(0) = \frac{1}{2} \times 2 \times (0)^2 = 0 \, \text{J} \] Thus, the increase in kinetic energy is: \[ \Delta K = K(1) - K(0) = 64 \, \text{J} - 0 \, \text{J} = 64 \, \text{J} \] ### Final Answer The increase in kinetic energy one second after the start of motion is **64 Joules**. ---

To solve the problem step by step, we need to find the increase in kinetic energy of the body one second after the start of motion. ### Step 1: Identify the displacement function The displacement of the body is given by the equation: \[ x = 2t^4 + 5 \] ### Step 2: Find the velocity function To find the velocity, we need to differentiate the displacement function with respect to time \( t \): ...
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