Electric power is measured in
a)watts or kilowatts.
b)amperes or milliamperes.
c)ohms or megohms.
d) volts or megavolts.
[Ques. 2] A celestial object called a pulsar emits its light in short bursts that are synchronized with its rotation. A pulsar in the Crab Nebula is rotating at a rate of 30 revolutions/second. What is the maximum radius of the pulsar, if no part of its surface can move faster than the speed of light (3 108 m/s)?
[Ques. 3] Electric current is measured in which SI units?
a) watts.
b) joules.
c) amperes.
d) coulombs.
[Ques. 4] A direct current
a) often changes direction as it flows through a conductor.
b) may change in magnitude but always flows in the same direction in a conductor.
c) must always remain constant in magnitude but can travel in any direction through a conductor.
d) can be used in a circuit with a transformer to change the voltage in that circuit.
[Ques. 5] A horizontal force of magnitude 6.5 N is exerted tangentially on a Frisbee of mass 32 grams and radius 14.3 cm. Assuming the Frisbee, a uniform disk, is originally at rest and the force is exerted for 0.08 s, determine the angular velocity of rotation about the central axis when the Frisbee is released.
[Ques. 6] Ohms law states
a) a relationship between voltage, current and charge.
b) that less current flows when a higher voltage is applied.
c) that the more resistance in a circuit, the more electric current will flow if the voltage is kept constant.
d) that the current in an electric circuit increases if the potential difference across the circuit is increased.
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[Ques. 7] Resistance
a) is measured in amperes.
b) is the opposition to the flow of electric current.
c) is the driving force that moves electrons in
conductors.
d) is not affected by temperature changes.
[Ques. 8] The net work done in accelerating a propeller from rest to an angular velocity of 200 rad/s is 3 000 J. What is the moment of inertia of the propeller?
[Ques. 9] Electric voltage is defined as
a)charge transfer per unit time.
b)work per unit charge.
c)resistance per unit charge.
d)work per unit time.
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[Ques. 10] A solid sphere, a solid cylinder, a spherical shell, and a hoop all have the same mass and radius. Each are rolling on a horizontal surface with the same center of mass speed, and then they roll up identical inclines. Which one goes the greatest distance up its incline?
a. the hoop
b. the solid sphere
c. the spherical shell
d. the cylinder
e. They all go the same distance up their inclines.