Phy Sci 6ed Chap 14 Review

MATH

if a 443 g soccer ball falls from a height of 3.5 m, what will its velocity be the moment it strikes the ground, assuming air resistance to be negligable.

• 8.29 m/s

• 10.21 m/s
• 3.45 m/s
• 5.67 m/s

If a 0.050 kg arrow was fired into the air with maximum gravitational potential energy of 34.3 J, what would be the maximum height that it reached?

• 25.6 meters
• 34.3 meters
• 69.9 meters

• 50.2 meters

Answer explanation

GPE = mgh

m= mass in kg

g = acceleration of gravity (9.81 m/s²)

h = height in meters

plug in the known values and solve for the missing varialbe

What is the kinetic energy of a 1300 kg muscle car traveling 23 m/s?

• 450,706 Joules
• 1300,23 Joules
• 23,1300 Joules
• 343,850 Joules

Answer explanation

KE = 1/2 mv²

Which of the following is a benefit of using hydroelectric dams for energy needs?

• they are inexpensive to maintain

• they clean the rivers

• they take up a lot of space

• the resevoir must be kept full for the dam to operate at full capacity

Which of the following is a disadvantage of using hydroelectric dams for energy?

• they are inexpensive to maintain

• they produce energy without pollution

• they take up a lot of space and require a dammable body of water

• they provide recreational benefits

which of the following is NOT one of the three main forms of fossil fuels

• coal

• natural gas

• petroleum

• wood

What energy transformation can be demonstrated by a heat lamp warming food.

• electrical energy converted to light

• electrical energy converted to heat

• light energy converted to heat

• all of these transformations are occuring

Why does a pendulum eventually stop swinging?

• all objects will naturally cease motion

• gravity causes objects to stop moving

• trick question, a pendulum will swing forever

• the swinging pendulum is losing energy due to air resistance

An energy resource that is easily replaced by natural methods

• nonrenewable energy resource

• limitless energy resource

• conservative energy resource

• renewable energy resource

"The total energy within a closed system remains constant over time"

• law of conservation of energy

• entropy

• Newton's 1st law of energy

• law of closed systems