Engineering in Kenya

# What is Physics Power?

Posted by on Apr 8, 2018 in Physics | 0 comments

From the physics point of view, physics power is the rate at which energy is used, transferred, or transformed. For instance, the rate at which a light bulb transforms electrical energy into light and heat is measured in watts. Power is directly proportional to voltage. The more the voltage, the more power is used per unit voltage.

Power is also the rate at which work is performed. This is because energy transfer can be used to do work, the output power of an electric motor is calculated as the angular velocity of its output shaft and the product of the torque the motor generates. The power expended to move a vehicle is the product of the velocity of the vehicle and the traction force of the wheels.

# Calculation of Physics Power

The work done is defined as integral power over time. Calculation of work is said to be “path dependent.” since this essential relays on the trajectory of the point of application of the force and torque.

Examples of Ansel Adams Boulder Dam Physics Power Units

Power is energy over time. The watt (W) is equal to one joule per second. Watt is the SI units of power. Other units of power include metric horsepower (Pferdestärke (PS) or cheval vapeur, CV), ergs per second (erg/s), horsepower (hp), and foot-pounds per minute. 33,000 foot-pounds per minute is equivalent to the power required to lift 550 pounds by one foot in one second, and is equivalent to about 746 watts.

## Formula of Physics Power

Burning a kilogram of coal releases much more energy than a kilogram of TNT,[3].  TNT delivers far more power than the coal because its reaction releases energy much more quickly. If we take? W as the amount of work performed during a period of time of duration? t, then the average power Pavg over that period is given by the formula: P_mathrm{avg} = frac{Delta W}{Delta t},.

This gives the average amount of energy or work done converted per unit of time. When the context makes it clear, the average power is often simply called “power” .The limiting value of the average power as the time interval ?t approaches zero is therefore the instantaneous power.P =lim _{Delta trightarrow 0} frac{Delta W}{Delta t}= frac{dW}{dt}=lim _{Delta trightarrow 0} P_mathrm{avg} ,.

### Work in Relation to Physics Power

The amount of work done during a period of duration T is given by:    W = PT, When power P is constant, It is more customary using the symbol E rather than W in energy conversion content.

The product of an object’s velocity and the force on an object gives physics power. In mechanical systems, power is the combination of forces and movement. The time derivative of work is also mechanical power. The work done by a force F on an object traveling along a curve C in mechanics is given by; W_C = int_{C}bold{F}cdot bold{v}dt     = int_{C} bold{F} cdot mathrm{d}bold{x}.

In the above formula, v is the velocity and x defines the path C along this path. Instantaneous power is yielded by the equation for work; P (t) = cdotmath{F} mathbf{v}.Physics can get even more interesting as you study more about physics power, we will study more in my next article.