Physics Final
Which has more weight -- a liter of ice or a liter of water?
A liter of water weighs more than a liter of ice.
Which statement is correct?
Current flows through a circuit.
A 10-N falling object encounters 4 N of air resistance. The magnitude of the net force on the object is
6 N
An apple weighs 1 N. The magnitude of net force on the apple when it is in free-fall is
1 N
Which has more volume -- a kilogram of gold or a kilogram of aluminum?
1 kg of aluminum has more volume.
Careful: On the surface of Jupiter, where the acceleration due to gravity is about three times that of Earth, a 100-kg rock would have a mass of about
100 kg
The current through a 10 ohm resistor connected to a 120-V power supply is
12 A
A jumbo jet has a mass of 100,000 kg. The thrust for each of four engines is 50,000 N. What is the jet's acceleration in meters per second per second when taking off?
2
A rock suspended by a weighing scale weighs 5 N out of water and 3 N when submerged in water. What is the buoyant force on the rock?
2 N
A 4 ohm resistor is connected in parallel with a 6 ohm resistor. This combination produces an equivalent resistance of
2.4 ohms
The current through two identical light bulbs connected in series is 0.25 A. The voltage across both bulbs is 110 V. The resistance of a single light bulb is
220 ohms
The electric power of a lamp that carries 2 A at 120 V is
240 W
A girl pulls on a 10-kg wagon with a constant force of 30 N. What is the wagon's acceleration in meters per second per second?
3.0
In a deep dive, a whale is appreciably compressed by the pressure of the surrounding water. What happens to the whale's density?
Its density increases.
What if the ice cube has many air bubbles?
The water level at the side of the glass is unchanged.
When an ice cube in a glass of water melts, does the water level in the glass rise, fall, or remain unchanged?
The water level at the side of the glass is unchanged.
How about if the ice cube contains many grains of heavy sand?
The water level at the side of the glass will fall slightly.
How does the weight of a falling body compare with the air resistance it encounters after it reaches terminal velocity?
The weight of the falling body is equal to air resistance.
How does the weight of a falling body compare with the air resistance it encounters before it reaches terminal velocity?
The weight of the falling body is greater than air resistance.
An ampere is a unit of electrical
current
When a light switch is turned on in a dc circuit, the average speed of electrons in the lamp is
less than 1 cm/s.
Your weight is
the gravitational attraction between you and the Earth.
