Work and Energy Concepts Flashcard

Front

What is Kinetic Energy?

Back

Kinetic Energy (KE) is the energy possessed by an object due to its motion, calculated using the formula: KE = \frac{1}{2}mv^2, where m is mass and v is velocity.

Front

Calculate the Kinetic Energy of a 5 kg object moving at 3 m/s.

Back

KE = \frac{1}{2} \times 5 \times (3)^2 = 22.5 J.

Front

What is Gravitational Potential Energy?

Back

Gravitational Potential Energy (PE) is the energy an object possesses due to its position in a gravitational field, calculated using the formula: PE = mgh, where m is mass, g is acceleration due to gravity, and h is height.

Front

Calculate the Gravitational Potential Energy of a 2 kg object raised to a height of 10 m (g = 9.8 m/s²).

Back

PE = 2 \times 9.8 \times 10 = 196 J.

Front

What is the definition of Work in physics?

Back

Work is defined as the product of the force applied to an object and the distance over which that force is applied in the direction of the force. It is calculated as: W = Fd, where W is work, F is force, and d is distance.

Front

When is work done by a force?

Back

Work is done when the force is applied in the direction of the motion of the object. Specifically, work is done only when the force is parallel to the direction of motion.

Front

Calculate the work done by a force of 15 N acting over a distance of 2 m in a direction perpendicular to the force.

Back

W = Fd \cos(90°) = 15 \times 2 \times 0 = 0 J.

Front

Calculate the work done when a force of 10 N is applied to move an object 5 meters in the direction of the force.

Back

W = Fd = 10 \times 5 = 50 J.

Front

What is the unit of Work in the International System of Units (SI)?

Back

The unit of Work is the Joule (J), which is defined as one Newton meter (1 J = 1 N·m).

Front

What is the relationship between Work and Energy?

Back

Work done on an object results in a change in its energy. If work is done on an object, its energy increases; if work is done by the object, its energy decreases.