physics sem 2
A neutral metal sphere is touched by a negatively charged metal rod. During the process, electrons are transferred from the _____ to the _____ and the sphere acquires a _____ charge.
charged rod; neutral sphere; negative
Induction
charging objects through other objects by moving them close to the objects
Materials which charges move through easily are ______
conductors
The acceleration of a projectile at point 2 is
constant
The horizontal velocity of a projectile is
constant
As more lamps are put into a series circuit, the overall current in the circuit
decreases
The vertical velocity of a projectile is
decreasing on the way up and increasing on the way down
How will the electrostatic force be affected if the distance between 2 charges is tripled?
divided by 9
The change in momentum of an object is referred to as the
impulse
As more lamps are put into a parallel circuit, the overall current in the circuit
increases
For most conductors, as their length increases, their resistance
increases
Mountain climbers use nylon safety ropes due to their tendency to stretch considerably under stress. Why?
increases time of the fall, force decreases
When a boxer recognizes that she will be hit by an opposing fist, she rides the punch. Why?
increases time, decreases force
What is the safest place to be during an electrical storm
inside a metal cage
An object traveling a circle at constant speed has an
inward acceleration
The greater that Earth's radius is, the _________ that another object will be attracted to Earth
less
compared to thin wires, electrical resistance in thick wires is
less
A neutral electroscope is touched with a positively charged rod. After the rod is removed the electroscope is charged _________ because of ____________
positively; conduction
A neutral electroscope is touched with a positively charged rod. After the rod is removed the electroscope is charged ____________ because of _____________
positively; conduction
fuses and circuit breakers are used to
protect us, prevent overloading, keep wires from getting overheated, break the circuit when too much current is being used
How will the electrostatic force be affected if the distance is halved?
quadrupled
The strength of an electric field gets ____ as you get closer to the charge
stronger
Conduction
the direct transfer of heat from one substance to another substance that it is touching.
A physics teacher rubs a glass object and a felt cloth together and the glass becomes positively charged. What is true about this?
the felt became charged negatively during the rubbing process
The "universal" of Newton's law of universal gravitation is a common source of confusion. The universal means that _____.
the force of gravity acts between all objects - not just between the Earth and an object, but even between two people. All objects with mass attract.
A 60-W light bulb and a 100-W light bulb are both rated at 120 V. Which light bulb has the larger resistance?
60-W
If two electrons are released near each other they will move ______________. As they move, the force between them will become ___________.
away from each other; weaker
A device that can indicate the presence of a charged object is a(n) ________
electroscope
A boxer rolls with the punch, in the same way as a receiver that allows his hands to move with the football as it is being caught. This is done to decrease the ______ by increasing the __________.
force; impact t
When objects are charged, one object gains electrons, and the other object ________ electrons. The total amount of charge is ___________.
loses; constant
The more mass that an object is, the ________ that the object will be attracted to Earth
more
The more massive the Earth is, the _________ that another object will be attracted to Earth
more
How will the electrostatic force be affected if both charges are tripled?
multiplied by 9
A positively charged object can attracted a _____ object
negative & neutral
If an object gains electrons its charge becomes more ________. If an object loses electrons its charge becomes more ___________.
negative; positive
A rubber balloon possesses a positive charge. If brought near and touched to the door of a wooden cabinet, it sticks to the door. This does not occur with an uncharged balloon. These two observations can lead one to conclude that the wall is _____.
negatively charged
A positively charged rod is brought near an electroscope. As a result of doing this, the electroscope leaves move apart. What is the charge of the electroscope?
neutral
Do astronauts have weight in space?
no, there is gravity too
electrical devices in our homes are connected in
parallel
If a proton and an electron are released near each other they will move ___________. As they move, the force between them will become __________.
towards each other; stronger
The strength of an electric field gets ________ as the source charge gets weaker
weaker
In order to form an electric circuit, you need to have
wires, power source, light bulb, complete path for current
