physics exam Flashcards
What is the definition of physics?
Physics is the study of matter, energy, and the interactions between them.
True or False: The SI unit for mass is the kilogram.
True
What is the formula for calculating speed?
Speed = Distance / Time
Fill in the blank: The standard unit of distance in the SI system is the ___.
meter
What is the difference between scalar and vector quantities?
Scalar quantities have magnitude only, while vector quantities have both magnitude and direction.
What is the formula for acceleration?
Acceleration = Change in Velocity / Time
True or False: Velocity is a scalar quantity.
False
What does the slope of a distance-time graph represent?
The slope represents speed.
What is the unit of force in the SI system?
Newton
Fill in the blank: The force of gravity acting on an object is called its ___.
weight
What is Newton’s First Law of Motion?
An object at rest stays at rest and an object in motion stays in motion unless acted upon by a net external force.
What is the formula for calculating momentum?
Momentum = Mass x Velocity
True or False: The unit of energy is the Joule.
True
What is the principle of conservation of energy?
Energy cannot be created or destroyed, only transformed from one form to another.
What is kinetic energy?
Kinetic energy is the energy of an object due to its motion.
What is the formula for gravitational potential energy?
Potential Energy = Mass x Gravity x Height
What is the difference between speed and velocity?
Speed is scalar and does not have direction, while velocity is a vector and includes direction.
Fill in the blank: The acceleration due to gravity on Earth is approximately ___.
9.81 m/s²
What does a flat line on a velocity-time graph indicate?
A flat line indicates constant velocity.
What is the formula for calculating work done?
Work = Force x Distance x cos(θ)
True or False: A heavier object falls faster than a lighter object in a vacuum.
False
What is the definition of acceleration?
Acceleration is the rate of change of velocity over time.
What is the unit of acceleration in the SI system?
m/s²
Fill in the blank: The area under a velocity-time graph represents ___.
displacement
What is the difference between elastic and inelastic collisions?
In elastic collisions, kinetic energy is conserved; in inelastic collisions, it is not.
What is the law of universal gravitation?
Every point mass attracts every other point mass with a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers.
Fill in the blank: The acceleration of an object is directly proportional to the ___.
net force acting on it
What is the unit of energy in the SI system?
Joule
What does friction do in a motion scenario?
Friction opposes the motion of objects.
What is centripetal force?
Centripetal force is the net force that acts on an object moving in a circular path, directed towards the center of the circle.
True or False: Work can be done even if there is no movement.
False
What is the difference between mass and weight?
Mass is the amount of matter in an object, while weight is the force of gravity acting on that mass.
What is the formula for calculating average speed?
Average Speed = Total Distance / Total Time
Fill in the blank: The gravitational force between two objects depends on their masses and the ___.
distance between them
What does an object’s inertia depend on?
Inertia depends on the object’s mass.
What is the definition of a free fall?
Free fall is the motion of an object under the influence of gravitational force only.
True or False: Energy can be transformed from one form to another.
True
What is the principle of momentum conservation?
The total momentum of a closed system remains constant if no external forces act on it.
What is the definition of displacement?
Displacement is the vector quantity that represents the change in position of an object.
True or False: Speed is a scalar quantity.
True
Fill in the blank: The formula for calculating average velocity is __________.
average velocity = total displacement / total time
What is the difference between distance and displacement?
Distance is a scalar quantity representing the total path length traveled, while displacement is a vector quantity indicating the shortest path from the initial to the final position.
What is the formula for calculating acceleration?
Acceleration = (final velocity - initial velocity) / time
Multiple Choice: Which of the following is NOT a unit of acceleration? A) m/s² B) km/h² C) m/s D) ft/s²
C) m/s
What does a negative acceleration indicate?
A negative acceleration indicates that an object is slowing down.
True or False: An object can have a constant speed but still be accelerating.
True
Fill in the blank: The area under a velocity-time graph represents __________.
displacement
What is the significance of the slope of a position-time graph?
The slope of a position-time graph represents the velocity of the object.
Multiple Choice: Which of the following equations represents uniformly accelerated motion? A) v = u + at B) v = u + 1/2at² C) s = ut + 1/2at² D) All of the above
D) All of the above
Define the term ‘free fall’.
Free fall is the motion of an object under the influence of gravitational force only.
What is the acceleration due to gravity on Earth?
The acceleration due to gravity on Earth is approximately 9.81 m/s².
True or False: The trajectory of a projectile is always a straight line.
False
Fill in the blank: The maximum height of a projectile occurs when its __________ is zero.
vertical velocity
What are the two components of projectile motion?
The horizontal component and the vertical component.
Multiple Choice: Which factor does NOT affect the range of a projectile? A) Launch angle B) Initial velocity C) Air resistance D) Mass of the projectile
D) Mass of the projectile
What is the principle of conservation of momentum?
The principle states that the total momentum of a closed system remains constant if no external forces act on it.
True or False: Momentum is a scalar quantity.
False
Fill in the blank: The formula for momentum is __________.
momentum = mass × velocity
What is an elastic collision?
An elastic collision is one in which both momentum and kinetic energy are conserved.
Multiple Choice: In an inelastic collision, which of the following is true? A) Total kinetic energy is conserved B) Total momentum is conserved C) Both A and B D) None of the above
B) Total momentum is conserved
What is the role of a force in relation to motion?
A force is any interaction that, when unopposed, will change the motion of an object.
True or False: A net force of zero indicates that an object is at rest.
False
Fill in the blank: Newton’s first law states that an object at rest will remain at rest, and an object in motion will remain in motion unless acted upon by a __________.
net external force
What is the formula for calculating force?
Force = mass × acceleration
What is the formula for calculating kinetic energy?
Kinetic energy (KE) = 1/2 mv², where m is mass and v is velocity.
True or False: Potential energy is the energy an object has due to its position.
True
Fill in the blank: The law of conservation of energy states that energy cannot be __________ or __________.
created, destroyed
What unit is used to measure energy?
Joule (J)
What is the difference between elastic and inelastic collisions?
In elastic collisions, kinetic energy is conserved; in inelastic collisions, kinetic energy is not conserved.
Multiple Choice: Which of the following is NOT a form of energy? A) Thermal B) Chemical C) Time D) Kinetic
C) Time
What is the gravitational potential energy formula?
Gravitational potential energy (PE) = mgh, where m is mass, g is acceleration due to gravity, and h is height.
True or False: Work is defined as the product of force and displacement in the direction of the force.
True
Fill in the blank: The work done on an object is equal to the change in its __________.
energy
What is the work-energy principle?
The work done on an object is equal to the change in its kinetic energy.
Multiple Choice: What is the unit of power? A) Joule B) Watt C) Newton D) Meter
B) Watt
What does the term ‘power’ refer to in physics?
Power refers to the rate at which work is done or energy is transferred.
True or False: A machine can create energy.
False
What is the efficiency of a machine?
Efficiency is the ratio of useful work output to total work input, usually expressed as a percentage.
Fill in the blank: The formula for calculating efficiency is __________.
(Useful work output / Total work input) x 100%
What is an example of a non-conservative force?
Friction
Multiple Choice: Which of the following forms of energy is associated with motion? A) Thermal B) Kinetic C) Potential D) Chemical
B) Kinetic
What is the principle of conservation of momentum?
The total momentum of a closed system remains constant if no external forces act on it.
True or False: Momentum is a vector quantity.
True
Fill in the blank: The formula for momentum is __________.
p = mv, where p is momentum, m is mass, and v is velocity.
What is the relationship between impulse and momentum?
Impulse is equal to the change in momentum of an object.
Multiple Choice: Which of the following is an example of a scalar quantity? A) Velocity B) Force C) Speed D) Acceleration
C) Speed
What is the definition of work in physics?
Work is done when a force causes displacement in the direction of the force.
True or False: The net work done on an object is equal to the object’s change in kinetic energy.
True
Fill in the blank: The unit of work is __________.
Joule (J)
What is the formula for calculating gravitational potential energy?
PE = mgh
Multiple Choice: Which of the following does NOT affect the gravitational potential energy of an object? A) Mass B) Height C) Speed D) Gravity
C) Speed
What is the effect of increasing the height of an object on its potential energy?
Increasing the height increases the gravitational potential energy.
True or False: In a vacuum, all objects fall at the same rate regardless of mass.
True
Fill in the blank: The acceleration due to gravity on Earth is approximately __________.
9.81 m/s²
What is the definition of a conservative force?
A conservative force is one where the work done is independent of the path taken and only depends on the initial and final positions.
Multiple Choice: An example of a conservative force is: A) Friction B) Tension C) Gravitational force D) Air resistance
C) Gravitational force
What is the relationship between energy and work?
Energy is the capacity to do work, and work is done when energy is transferred.
True or False: An object at rest has kinetic energy.
False
Fill in the blank: The total mechanical energy of an object is the sum of its __________ and __________ energy.
kinetic, potential
What is the formula for calculating power?
Power = Work / Time
Multiple Choice: In a perfectly elastic collision, which of the following is conserved? A) Kinetic Energy B) Momentum C) Both A and B D) Neither A nor B
C) Both A and B
What does it mean for a collision to be inelastic?
In an inelastic collision, kinetic energy is not conserved, but momentum is.
True or False: The work-energy theorem relates work and kinetic energy.
True
Fill in the blank: The principle of work-energy states that the work done on an object is equal to the __________ in kinetic energy.
change
What is a common unit for measuring power in the International System of Units (SI)?
Watt (W)
Multiple Choice: Which of the following statements is true regarding energy? A) Energy can be created B) Energy can be destroyed C) Energy can change forms D) None of the above
C) Energy can change forms
What type of energy is stored in a compressed spring?
Elastic potential energy
True or False: A system with higher efficiency does less useful work.
False
Fill in the blank: The mechanical energy of a system is conserved when only __________ forces are acting.
conservative
What is the significance of the area under a force vs. displacement graph?
The area under the graph represents the work done on the object.
Multiple Choice: Which of the following quantities has both magnitude and direction? A) Work B) Energy C) Force D) Power
C) Force
What happens to the potential energy of an object as it is lifted higher in a gravitational field?
The potential energy increases.
True or False: The conservation of energy principle applies to all types of energy transformations.
True
Fill in the blank: The formula for calculating impulse is __________.
Impulse = Force x Time
What is the result of a collision between two objects with equal mass and equal but opposite velocities?
They will come to rest if the collision is perfectly elastic.
Multiple Choice: Which of the following best describes thermal energy? A) Energy due to motion B) Energy stored in chemical bonds C) Energy due to temperature D) Energy due to position
C) Energy due to temperature
What is the relationship between temperature and thermal energy?
As temperature increases, thermal energy increases.
True or False: All forms of energy can be converted into thermal energy.
True
Fill in the blank: The conservation of momentum applies to __________ systems.
closed
What is the effect of doubling the mass of an object on its kinetic energy if its velocity remains constant?
The kinetic energy will double.
Multiple Choice: Which of the following is an example of an energy transformation? A) A car accelerating B) A light bulb glowing C) A battery powering a device D) All of the above
D) All of the above
What is the potential energy of an object at a height of 10 m with a mass of 2 kg?
PE = mgh = 2 kg x 9.81 m/s² x 10 m = 196.2 J
True or False: The energy of a system can change without external work being done.
True
Fill in the blank: The total energy of an isolated system remains __________.
constant
What is the purpose of a machine?
A machine is used to make work easier by changing the magnitude or direction of a force.
Multiple Choice: Which type of energy is associated with the motion of particles in a substance? A) Kinetic B) Potential C) Mechanical D) Nuclear
A) Kinetic
What is the principle of conservation of momentum?
The total momentum of a closed system remains constant if no external forces act on it.
True or False: Inelastic collisions conserve kinetic energy.
False
Fill in the blank: The formula for momentum is _____ = mass × velocity.
p
What is impulse?
Impulse is the change in momentum, calculated as the product of force and the time duration over which it acts.
Multiple Choice: Which of the following is a scalar quantity? A) Force B) Velocity C) Mass D) Acceleration
C) Mass
What is the equation for calculating kinetic energy?
KE = 1/2 mv²
True or False: The work done on an object is equal to the change in its kinetic energy.
True
Fill in the blank: The law of conservation of energy states that energy cannot be _____ or destroyed, only transformed.
created
What is the unit of work in the International System of Units (SI)?
Joule (J)
Multiple Choice: Which type of collision conserves both momentum and kinetic energy? A) Elastic B) Inelastic C) Perfectly inelastic D) All of the above
A) Elastic
What does the term ‘power’ refer to in physics?
Power is the rate at which work is done or energy is transferred.
True or False: Power is measured in watts.
True
Fill in the blank: The formula for power is _____ = work/time.
P
What is a projectile?
A projectile is an object that is thrown into the air with an initial velocity and is subject to the force of gravity.
Multiple Choice: Which of the following factors does not affect the range of a projectile? A) Launch angle B) Initial velocity C) Mass of the projectile D) Height of launch
C) Mass of the projectile
What is the horizontal component of a projectile’s velocity?
It remains constant throughout the motion.
True or False: The vertical motion of a projectile is influenced by gravity.
True
Fill in the blank: The maximum height of a projectile occurs at _____ degrees.
90
What is the formula for calculating the range of a projectile launched at an angle?
Range = (v² * sin(2θ)) / g
Multiple Choice: The acceleration due to gravity is approximately: A) 9.8 m/s² B) 10 m/s² C) 8.5 m/s² D) 11.2 m/s²
A) 9.8 m/s²
What is the difference between elastic and inelastic collisions?
Elastic collisions conserve both momentum and kinetic energy, while inelastic collisions conserve momentum but not kinetic energy.
True or False: In a perfectly inelastic collision, the colliding objects stick together after the collision.
True
Fill in the blank: The center of mass of an object is the point at which its mass can be considered to be _____ concentrated.
conveniently
What does it mean for a system to be in equilibrium?
A system is in equilibrium when the net force and net torque acting on it are both zero.
Multiple Choice: What type of energy does a compressed spring store? A) Kinetic energy B) Potential energy C) Thermal energy D) Chemical energy
B) Potential energy