Physics students are performing an experiment and slide a hockey puck off a horizontal desk that is 1.2m high. The initial speed of the puck is 1.5m/s. Determine the final velocity(including the angle) the puck has the moment it hits the ground.

Answer 1

To solve this problem, we need to consider the conservation of energy.

The initial kinetic energy of the puck is given by the formula:

KEi = (1/2)mv^2

where m is the mass of the puck and v is the initial velocity.

The final potential energy of the puck is given by the formula:

PEf = mgh

where m is the mass of the puck, g is the acceleration due to gravity (approximately 9.8 m/s^2), and h is the height of the desk.

Since the energy cannot be created or destroyed, the initial kinetic energy is equal to the final potential energy:

KEi = PEf

(1/2)mv^2 = mgh

Cancelling out the mass:

(1/2)v^2 = gh

Rearranging the equation:

v^2 = 2gh

Taking the square root of both sides:

v = √(2gh)

Substituting the given values:

v = √(2 * 9.8 m/s^2 * 1.2 m)

v ≈ √(23.52 m^2/s^2)

v ≈ 4.85 m/s

The final velocity of the puck just before it hits the ground is approximately 4.85 m/s.