test2
A projectile is launched at an angle of 15 degree above the horizontal and lands downrange. what other projectile angle for the same speed would produce the downrange distance?
75 degree
A projectile hits the surface of the earth at some point, if its speed is:
<8000m/s
The principle which states that an immersed body is buoyed by a force equal to the weight of the fluid it displaces is:
Archimedes' principle
A coin and a feather dropped in a vacuum will have the same momentum.
False
A machine with a power output of 500W, for every input of 1000W, is said to have an efficiency of 25%.
False
Any completely immersed body displaces a quantity of fluid equal to its own weight.
False
Barometer is any device that measures the density of materials.
False
Escape speed from a planet decreases with increase in the mass of the planet.
False
Every 8000m, the surface of the Earth drops an approximate vertical distance of 20m.
False
Ice tends to form at the bottom of bodies of water.
False
Kinetic energy is energy of an object because of its location.
False
Kinetic energy is the stored energy that a body possesses because of its position.
False
The critical speed at which a projectile outruns gravity is called terminal speed.
False
The horizontal speed of a projectile is influenced by gravity.
False
The pressure in liquid decreases with depth.
False
Work is the product of force and the distance through which the force moves.
False
Work is the product of force and time
False
A completely submerged object displaces its volume of fluid.
True
An Earth satellite is simply a projectile freely falling around the Earth.
True
An astronaut in space feels weightless.
True
If you double the velocity of a moving object with constant mass, its momentum will double.
True
In circular orbit, the speed of a satellite is the same everywhere.
True
It takes relatively short time to boil water at higher altitude than at sea level.
True
Potential energy of an object is because of its location.
True
Salty water is denser than fresh water.
True
The density of fish is equal to the density of water.
True
Weightlessness is the condition encountered in free fall wherein a support force is lacking.
True
A feather and a coin dropped in a vacuum fall with equal:
acceleration
In the vacuum of outer space, there is no:
atmospheric pressure
Any device that measures atmospheric pressure is called:
barometer
A freight train rolls along a track with considerable momentum. If it rolls at the same speed but has twice as much mass, its momentum is:
double
If the mass of an object were to double while its volume remains the same, its density would:
double
The critical speed at which a projectile outruns gravity is called:
escape speed
A car that travels twice as fast as another, when breaking to a stop will skid:
four times as far
A heavy truck and a small car rolling down a hill at the same speed are forced to stop in the same amount of time. Compared to the force that stops the car, the force needed to stop the truck is
greater
If the volume of an object were to double while its mass stays the same, its density would:
halve
Atmospheric pressure is:
higher at sea level than at the top of a very high mountain
Two objects move toward each other because of gravity. as the objects get closer, the force between them
increases
When the distance between two stars decreases by half, the force between them:
increases four times as much
Ice floating on water indicates that the the density of ice is:
less than the density of water
According to Newton, the greater the distance between masses of interacting objects, the:
less the gravitational force between them
An object that has potential energy may have this energy because of its:
location
When you are on the way of a fast moving object and can't get out of its way, you will suffer a smaller force of impact if you decrease its momentum over a:
long time
Force per unit area is called:
pressure
Any object that moves through the air or through space under the influence of gravity is called:
projectile
The force that an object exerts on a supporting surface is called:
support force
If you push an object just as far while applying twice the force, you do:
twice as much work
If you do work on an object in half the time, your power output is:
twice the usual power
When a chocolate bar is cut in half, its density is:
unchanged
A feeling encountered in free fall wherein a support force is lacking is called:
weightlessness