Efficiency = Wout/Win = (load)(load distance)/(effort)/(effort distance) Wout = the product of load & load distanceWin = the product of work effort & effort distanceload = how much the object weighsload distance = how far you want the object to goeffort = how much work you put in to move the objecteffort distance = how far you have to move the object for a given amount of effort

MCAT Physics: Mastering Key Equations

1. What is the formula for Kinetic Energy?

K = m + v

K = m - v

K = kinetic energym = massv = velocity

K = m * v

The correct formula for Kinetic Energy is K = 0.5 * m * v^2, where K represents kinetic energy, m represents mass, and v represents velocity. This formula accounts for the relationship between mass and velocity in calculating the kinetic energy of an object.

Explanation

The correct formula for Kinetic Energy is K = 0.5 * m * v^2, where K represents kinetic energy, m represents mass, and v represents velocity. This formula accounts for the relationship between mass and velocity in calculating the kinetic energy of an object.

2. What is Gravitational Potential Energy?

B. Energy stored in the bonds between atoms of an object

C. Energy related to the temperature of an object

A. Energy associated with the rotation of an object

Gravitational Potential Energy is specifically defined as the energy an object possesses due to its position in a gravitational field, not related to rotation, atomic bonds, or temperature.

Explanation

Gravitational Potential Energy is specifically defined as the energy an object possesses due to its position in a gravitational field, not related to rotation, atomic bonds, or temperature.

3. What is the definition of Work in mechanical terms?

W = F x d x θ

W = F / d

W = F + d

In mechanical terms, work is defined as the product of force and displacement, which can also be expressed as W = Fd cosθ.

Explanation

In mechanical terms, work is defined as the product of force and displacement, which can also be expressed as W = Fd cosθ.

4. What is the definition of Power?

Power is the distance an object travels over a period of time.

Power is the force exerted on an object.

P = W/t = ΔE/t P = powerW = workt = timeΔE = change in energy

Power is the amount of energy stored in an object.

Power is defined as the rate at which work is done or the rate at which energy is transferred or converted. It is measured in watts (W) and is calculated by dividing work done (W) by the time taken (t) or by dividing the change in energy (ΔE) by time taken (t).

Explanation

Power is defined as the rate at which work is done or the rate at which energy is transferred or converted. It is measured in watts (W) and is calculated by dividing work done (W) by the time taken (t) or by dividing the change in energy (ΔE) by time taken (t).

5. What is Elastic Potential Energy?

U = k/x

U = 1/2k^2x

U = kx^2

Elastic potential energy is the energy stored in an object when it is deformed (stretched or compressed). The correct formula for elastic potential energy is U = 1/2kx^2, where U is the potential energy, k is the spring constant, and x is the displacement from equilibrium.

Explanation

Elastic potential energy is the energy stored in an object when it is deformed (stretched or compressed). The correct formula for elastic potential energy is U = 1/2kx^2, where U is the potential energy, k is the spring constant, and x is the displacement from equilibrium.

6. What does the Work-Energy Theorem state?

Wnet = 0

Force = Mass x Acceleration

Work = Kinetic Energy^2

The Work-Energy Theorem states that the net work done on an object is equal to the change in kinetic energy of that object.

Explanation

The Work-Energy Theorem states that the net work done on an object is equal to the change in kinetic energy of that object.

7. What is efficiency?

Efficiency = load/load distance

Efficiency = Win/Wout

Efficiency = effort/effort distance

Efficiency is a measure of how much useful work a machine generates for a given amount of work put into it. The correct formula for efficiency involves the ratio of output work (Wout) to input work (Win), taking into account the product of load, load distance, effort, and effort distance.

Explanation

Efficiency is a measure of how much useful work a machine generates for a given amount of work put into it. The correct formula for efficiency involves the ratio of output work (Wout) to input work (Win), taking into account the product of load, load distance, effort, and effort distance.

8. What is the formula for total mechanical energy?

E = U - K (E = total mechanical energy, U = potential energy, K = kinetic energy)

E = U * K (E = total mechanical energy, U = potential energy, K = kinetic energy)

E = U ÷ K (E = total mechanical energy, U = potential energy, K = kinetic energy)

E = U + K E = total mechanical energyU = potential energyK = kinetic energy

Total mechanical energy (E) is the sum of potential energy (U) and kinetic energy (K), therefore the correct formula is E = U + K.

Explanation

Total mechanical energy (E) is the sum of potential energy (U) and kinetic energy (K), therefore the correct formula is E = U + K.

9. Conservation of Mechanical Energy

ΔE = ΔU. This equation only considers the change in potential energy, not the total mechanical energy conservation.

ΔE = ΔU + ΔK > 0. This equation does not represent the conservation of mechanical energy.

The conservation of mechanical energy is represented by the equation ΔE = ΔU + ΔK = 0, where ΔE is the change in internal energy, ΔU is the change in potential energy, and ΔK is the change in kinetic energy. This equation ensures that the total mechanical energy in a system remains constant.

Explanation

The conservation of mechanical energy is represented by the equation ΔE = ΔU + ΔK = 0, where ΔE is the change in internal energy, ΔU is the change in potential energy, and ΔK is the change in kinetic energy. This equation ensures that the total mechanical energy in a system remains constant.

10. What is the formula for calculating the work done by nonconservative forces (friction, air resistance, viscous drag)?

Wnonconservative = ΔE = ΔU - ΔK

Wnonconservative = ΔE = ΔU * ΔK

Wnonconservative = ΔE = ΔU / ΔK

The work done by nonconservative forces is calculated as the change in total mechanical energy, which is the sum of the changes in potential and kinetic energy.

Explanation

The work done by nonconservative forces is calculated as the change in total mechanical energy, which is the sum of the changes in potential and kinetic energy.

11. What is Mechanical Advantage?

A. Mechanical Advantage = Fin/Fout

B. Mechanical Advantage = Fin * Fout

C. Mechanical Advantage = Fout + Fin

Mechanical advantage is calculated by dividing the output force (Fout) by the input force (Fin). It is a measure of the force amplification achieved by using a simple machine. The correct formula to calculate mechanical advantage is Fout/Fin.

Explanation

Mechanical advantage is calculated by dividing the output force (Fout) by the input force (Fin). It is a measure of the force amplification achieved by using a simple machine. The correct formula to calculate mechanical advantage is Fout/Fin.