Dynamics
An object moving with constant velocity indicates that the forces acting on it are __________.
balanced
unbalanced
all acting in one direction
increasing in strength
A magician pulls a tablecloth out from a fully set dining table, leaving the dishes and glasses intact. This trick is best explained by...
magic.
Newton's Third Law.
Newton's First Law.
Newton's Second Law.
On a smooth horizontal surface, two objects are connected by a light string passing over a pulley; if one object has twice the mass of another and external forces remain absent, what happens when they are released from rest?
The heavier object accelerates downward while pulling up lighter one.
Both objects move with accelerations proportional to their masses.
The system rotationally accelerates around pulley center due to unequal masses.
They stay at rest because net external horizontal forces are zero.
What is the approximate net force of a 50 kg box with an additional weight of 5 kg given that the box is at rest?
500 N
50 N
550 N
0 N
A cartridge is fired from a gun at a target which is suspended by a light string in an airless space. How will the course of the bullet change once it hits the target?
The bullet will embed in the target and both will move together in the same direction as the bullet's original flight.
The bullet passes through the target, continuing its path in the same direction but at a slower speed.
The target is pushed back but the bullet continues forward without any change in speed or direction.
The bullet will rebound off the target and move in the opposite direction with decreased velocity.
A car travels on a straight road without any turns or obstacles. What can we infer about the net force acting on the car?
The net force is zero
There must be a downward force equal to the weight
A forward force applied by the engine balances air resistance and friction
Sideways forces have zero value since the car isn't turning
Rank the objects from greatest to least inertia. Block A : 10 kg at -2 m/s Block B : 2 kg at 20 m/s Block C : 4 kg at 10 m/s Block D : 40 kg at rest
D, A, C, B
B, A, C, D
B, C, A, D
D, A, B, C

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What happens when you increase the resistance of a resistor in a parallel circuit while keeping the remaining resistors exactly the same?
The current flow only in the newly added resistor decreases.
The current through all the resistors decreases.
The total current decreases while maintaining equal potential drops across all resistors.
There is no effect on the total current flow because it is independent of individual resistor resistance.
According to Newton's First Law, what will happen to an object at rest if no net force acts on it?
It will slowly come to a stop
It will begin to accelerate
It will move with a constant velocity
It will remain at rest
During a game of pool, when the cue ball strikes another stationary ball straight on, how does Newton's first law apply immediately after impact if both balls are identical?
Both balls move forward with half of the original speed maintaining total momentum but not kinetic energy split equally
The second ball stays in place as both balls absorb equal amounts of kinetic energy
The cue ball stops and transfers all its kinetic energy to the second ball
The cue ball continues moving at reduced speed, transferring only some kinetic energy while losing none itself