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A particle moves with a velocity v=(5hat...

A particle moves with a velocity `v=(5hati-3hatj + 6hatk) ms^(-1)` under the influence of a constant force
`F =(10hati + 10hatj + 20hath) N`, the instantaneous power applied to the particle is.

A

`200 W`

B

`320 W`

C

`140 W`

D

`170 W`

Text Solution

AI Generated Solution

The correct Answer is:
To find the instantaneous power applied to the particle, we can use the formula for power in terms of force and velocity, which is given by: \[ P = \mathbf{F} \cdot \mathbf{v} \] where \( P \) is the power, \( \mathbf{F} \) is the force vector, and \( \mathbf{v} \) is the velocity vector. ### Step-by-Step Solution: 1. **Identify the Force and Velocity Vectors:** - Given the force vector: \[ \mathbf{F} = 10 \hat{i} + 10 \hat{j} + 20 \hat{k} \, \text{N} \] - Given the velocity vector: \[ \mathbf{v} = 5 \hat{i} - 3 \hat{j} + 6 \hat{k} \, \text{m/s} \] 2. **Calculate the Dot Product:** - The dot product \( \mathbf{F} \cdot \mathbf{v} \) is calculated as follows: \[ \mathbf{F} \cdot \mathbf{v} = (10 \hat{i} + 10 \hat{j} + 20 \hat{k}) \cdot (5 \hat{i} - 3 \hat{j} + 6 \hat{k}) \] - This expands to: \[ = (10 \times 5) + (10 \times -3) + (20 \times 6) \] 3. **Perform the Multiplications:** - Calculate each term: \[ = 50 - 30 + 120 \] 4. **Combine the Results:** - Now, add the results together: \[ = 50 - 30 + 120 = 140 \] 5. **Final Result for Power:** - The instantaneous power \( P \) is: \[ P = 140 \, \text{W} \] ### Conclusion: The instantaneous power applied to the particle is **140 watts**.

To find the instantaneous power applied to the particle, we can use the formula for power in terms of force and velocity, which is given by: \[ P = \mathbf{F} \cdot \mathbf{v} \] where \( P \) is the power, \( \mathbf{F} \) is the force vector, and \( \mathbf{v} \) is the velocity vector. ### Step-by-Step Solution: ...
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