Physics · Work, Power & Energy
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Power is the dot product of
- A
Mass & velocity
- B
Force & velocity
- C
Force & energy
- D
Force and mass
Option B is the correct answer. The power exerted by a force is calculated as the dot product of the force vector and the velocity vector, P = F · v, where F is force and v is velocity. This formula signifies how quickly work is done or energy is transferred. Option A is incorrect because mass multiplied by velocity gives momentum, not power. Option C is incorrect because force and energy are not used together in a dot product to calculate power. Option D is incorrect because force and mass together relate to acceleration (F = ma) and not to power directly.
Option A is incorrect because power is not calculated as a product of mass and velocity; this combination relates to momentum.
Option B is correct because power is defined as the dot product of force and velocity, representing the rate at which work is done.
Option C is incorrect because force and energy are not combined through a dot product to calculate power; energy is a scalar quantity.
Option D is incorrect because force and mass are related by Newton's second law (F = ma), not through a dot product for calculating power.
Tagged under Physics · Work, Power & Energy · 2010