physics Flashcards
What is the standard unit of mass?
Kilogram
What is defined as the distance the light travels in a vacuum in 1/2999,792,458 second?
Meter
What is the SI unit of work?
Joule
What is the SI unit of power?
Watt
What is the SI unit of temperature?
Kelvin
What is the SI unit of luminous intensity?
Candela
What is the unit of relative intensity?
Unitless
What is the SI unit of pressure?
Pa
Which one is equivalent to the unit of “Pascal”?
N/m²
The pressure of 1bar is equivalent to how many Pascals?
100,000
What is the SI unit of intensity?
Watt/m²
What is the unit of potential difference?
Volt
Which of the following is equivalent to a volt?
Joule/Coulomb
One electron volt is equivalent to ______ joules.
1.6x10-¹⁹
What is the unit of capacitance?
Farad
1 Farad is equal to?
Coulomb/Volt
What is the unit of electric current?
Ampere
Which of the following is equivalent to the unit of “ampere”?
Coulomb/Second
What is the unit of resistance?
Ohm
Ohm is equivalent to?
Volt/ampere
What is the unit of luminous intensity?
Candela
What is the unit of luminous flux?
Lumen
Which of the following is equivalent to the unit “Candela”?
Lumen/steradian
What is the unit of luminous efficiency?
lumen/watt
What is the unit of illumination?
Lux
Lux is equivalent to which combination of units?
Lumen/m²
Footcandle is equivalent to which combination of units?
lumen/ft²
How many dynes are there in one newton?
100,000
What is an elemental unit of energy?
Quantum
What refers to the mass which is accelerated at the rate of one foot per second when acted on by a force of one pound?
slug
The size of some bacteria and living cells is in the order of?
Micrometer
The size of the largest atom is in the order of?
Nanometer
The mass of a grain of salt is in the order of?
miligram
1 Joule is equal to?
Newton-meter
1 Watt is equal to?
Newton-meter/ second
1 Horse power is equal to?
746
The “kilowatt-hour” is a unit of?
Work or energy
“Mole” is one of the SI base units. It measures.
Amount of substances
The English unit “slug” is a unit of?
Mass
How is sound intensity measured?
In decibels
An electron volt is the energy required by an electron that has been accelerated by a potential difference of how many volt?
1 Volt
What is a vector with a magnitude of one and with no unit
Unit vector
What is the purpose of a unit vector?
To describe the direction in space
What is another term for a scalar product of two vector?
Dot product
What is another term for a vector product of two vector?
Cross product
The scalar product of two perpendicular vectors is always.
equal to 0
The vector product of two parallel or antiparallel vector is always
equal to 0.
The vector product of any vector with itself is
equal to 0
What refers to physical quantities that are completely specified by just a number and a unit or physical quantities that have magnitudes only?
Scalar quantities
What refers to physical quantities that have a magnitude and a direction?
Vector quantities
Which is NOT a vector quantity.
•DISPLACEMENT
•VELOCITY
•ACCELERATION
•TIME
Time
Which is NOT a fundamental pyhsical quantity of mechanics?
• Length
•Mass
•Volume
•Time
Volume
What is an arrow line whose length is proportional to the magnitude of some vector quantity and whose direction is that of the quantity?
Vector
What is scaled drawing of the various forces, velocities or other vector quantities involved in the motion of a body
Vector diagram
The ______ of a moving object is the distance it covers in a time interval divided by the time interval.
Average speed
The rate at which velocity changes with timeis known as
Acceleration
“The work done by the net force on a particle equals the change in the particle’s kinetic energy.” This statement is known as.
Work-energy theorem
The _____ of a particle is equal to the total work that particle can do in the process of being brought to rest.
kinetic energy
Work is defined as the product of:
Force and displacement
What is defined as the time rate at which work is done?
Power
What is defined as any influence that can change the velocity of an object?
Force
What is a measure of the inertia of an object?
Mass
What is the property of matter which is the reluctance to change its state of rest or of uniform motion?
Inertia
“If no net force acts on it, an object at rest will remain at rest and an object in motion will remain in motion at constant velocity” this statement is the.
First law of motion
“The net force acting on an object equals the product of the mass and the acceleration of the object. The direction of the force is the same as that of the acceleration” This statement is the.
Second law of motion
“When an object exerts a force on another object, the second object exerts on the first a force of the same magnitude but in the opposite direction” this statement is the.
Third law of motion
What refers to the forces with which the earth attracts an object?
Weight
How many kilograms are there in 1slug?
14.6
What refers to an actual force that arises to oppose relative motion between contracting surfaces?
Friction
What refers to the force between two stationary surfaces in contact that prevents motion between them?
Static friction
What is the maximum value of the static friction?
Starting friction
What is TRUE between kinetic friction and static friction.
• Kinetic friction is always to static friction
•Kinetic friction is always less than static friction
•Kinetic friction is always greater than static friction
•Kinetic friction is equal to or greater than static friction
Kinetic friction is always less than static friction
What is another term for kinetic friction?
sliding friction
For the same materials in contact, what is TRUE between coefficient of static friction and coefficient of kinetic friction?
•Coefficient of static friction is always less than the coefficient of kinetic friction
•Coefficient of static friction is always equal to the coefficient of kinetic friction
•Coefficient of static friction is always greater than the coefficient of kinetic friction
•Coefficient of static friction may be greater than or less than the coefficient of kinetic friction
Coefficient of static friction is always greater than the coefficient of kinetic friction
Efficiency of a machine is the ratio of:
Power output to power input
What is the energy something possesses by virtue of its motion?
Kinetic energy
What is the energy something possesses by virtue of its mass?
Rest energy
What is the energy something possesses by the virtue of its position?
Potential energy
When the vector sum of the external forces acting on the system of particles equals to zero, the total linear momentum of the system
remains constant
What is conserved in an elastic collision?
Kinetic energy
In elastic collision, kinetic energy is conserved. This statement is:
True
When can we say that a collision is a completely inelastic?
When the two colliding objects stick together after impact
What will happen to the kinetic energy if it is a completely inelastic collisions?
It is lost to maximum value
Coefficient of restitution is the ratio of:
Relative speed after collision to relative speed before collision
What is the coefficient of restitution for a perfectly elastic collision?
1
What is the coefficient of restitution for a perfectly inelastic collisions?
0
The coefficient of resitution always applies
jointly to the colliding objects
“When the vector sum of the external forces acting on a system of particles equals zero, the total linear momentum of the system remaining constant.” this statement is known as:
Law of conservation of momentum
What refers to the product of the force and the time during which a force acts?
Impulse
Momentum is the product of
velocity and mass
Which of the following quantities is/are conserved during all types of collison?
•Kinetic Energy
•Velocity
•Momentum
•Force
Momentum
What refers to the force perpendicular to the velocity of an object moving along a curve path?
Centrifugal force
The centripetal force is:
directed toward the center of curvature of the path
What refers to the time needed by an object in uniform circular motion to complete an orbit?
Period
The centripetal acceleration of a particle in uniform motion is ______ to the radius of its path.
Inversely proportional
Gravitation occurs between all object in the universe by virtue of their.
Mass
“Every object in the universe attracts every other object with a force directly proportional to the product of their masses and inversely proportional to the square of the distance separating them”. This statement is known as:
Law of universal gravitation
The gravitational force of the earth on an object varies _______ the distance of the object from the center of the earth.
inversely as the square of
What type of energy is usually transmitted by rotary motion?
Mechanical energy
Angular momentum is the product of
Moment of inertia and angular speed
Rotating body has kinetic energy. This statement is.
Always true
“When the sum of the external torques acting on a system of particles is zero, the total angular momentum of the system remains constant”. This Statement is known as:
Conservation of angular momentum
what particles will experience tangential acceleration.
Those particles whose angular speed changes
The _______ of a body about a given axis is the rotational analog of mass of the body is distributed about the axis.
Moment of inertia
The _________ of a force about a particular axis is the product of the magnitude of the force and the perpendicular distance from the line of action of the force to the axis.
Torque
When the forces that act on an object have vector sum of zero, the object is said to be in
translational equilibrium
Which of the following is an example of a neutral equilibrium?
A cone its side
Which of the following is an example of a stable equilibrium?
a cone balanced on its base
A device that transmits force or torque is called
Machine
If a cone is balanced on its apex, it illustrates what type of equilibrium?
unstable equilibrium
When the net torque acting on an object is zero, the objects is in
rational equilibrium
Which of the following is NOT a basic machine?
•Lever
•inclined plane
•hydraulic press
•wedge
Hydraulic press
Where is the center of gravity of an object located?
It may sometimes be inside the object and sometimes outside the object
What is defined as the mass per unit volume
Density
What is defined as the weight per unit volume?
Weight density
All are value of the density of water except one. Which one?
•100kg/m³
•62.4 lb/ft³
•10 g/cm³
•9.81kN/m³
10g/cm³
The _______ of a substance is its density relative to that of water?
specific gravity
What is another term for specific gravity?
relative density
What is the average pressure of the earth’s atmosphere at sea level?
1.013 bar