Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Physics > Mechanics > Flashcards

Mechanics Flashcards

1
Q

what is meant by terminal velocity

A

when the forces acting on the falling object become balanced, the acceleration becomes zero and the object is moving at maximum velocity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is meant by friction

A

a resistance to motion between
an object and a surface or
an object moving through a fluid.
Friction is a force that acts in the opposite direction to the movement

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is Newton’s 3rd law?

A

for each force experienced by an object, the object exerts an equal and opposite force

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is Newton’s 2nd law?

A

F=ma
the resultant force is directly proportional to the rate of change of momentum and acts in the same direction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is Newton’s first law?

A

an object will remain in its current state of motion, unless acted on by a resultant force.
An object requires a resultant force to be able to accelerate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is the equation for momentum?

A

momentum = mass x velocity
p=mv

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

as well as impulse, what can also be described as the change of momentum?

A

force x time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what is impulse?

A

the change in momentum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are the units for impulse and momentum?

A

Ns and Kgm/s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does the area underneath a force-time graph represent?

A

impulse/change in momentum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the rate of work done equal to?

A

power

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is efficiency?

A

useful output/
total output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is meant by the principle of conservation of energy?

A

energy cannot be created or destroyed,
only transferred into other forms of energy
therefore, total energy in a closed system will always remain the same

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is the difference between mass and weight?

A

mass is scalar and is not dependent on the gravity acting upon it
weight is a vector and depends on the gravitational field strength

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the principle of moments?

A

for an object in equilibrium,
the sum of clockwise moments (about a pivot) is equal to the sum of anti clockwise moments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what does it mean for an object to be in equilibrium?

A

it is not accelerating
it is either stationary or moving at a constant velocity

17
Q

what is a moment and what is its equation?

A

a turning force:
force x perpendicular distance from the point to the line of action of the force

18
Q

what is meant by a couple?

A

a pair of equal and opposite coplanar forces

19
Q

what is meant by centre of mass?

A

the point through which all the mass of an object acts, for a uniform object the centre of mass is the centre of the object

20
Q

what is the change in displacement per unit of time?

A

velocity

21
Q

what is free fall?

A

where an object experiences an acceleration of g

22
Q

what is lift?

A

an upward force which acts on an objects travelling in a fluid

23
Q

what causes lift?

A

an object creating a change in the direction of fluid flow, and it acts perpendicular to the direction of fluid flow

24
Q

What are the properties of a vector quantity?

A

A vector quantity is one that has both a magnitude and a direction.
Examples include velocity, displacement and acceleration.

25
Q

what is an inelastic collision?

A

A collision in which the total kinetic energy of the system before the collision is not equal to the kinetic energy of the system after the collision.

26
Q

How do you find velocity on a displacement-time graph?

A

velocity is found by measuring the gradient of a tangent to a displacement-time graph

27
Q

what is the difference between mass and weight?

A

mass is scalar and is not dependant on the gravity acting upon it
weight is a vector and depends on the gravitational field strength
W=mg

28
Q

What does it mean for an object to be in equilibrium?

A

not accelerating, so either
stationary
or moving at a constant velocity

29
Q

what is a couple?

A

a pair of equal and opposite coplanar forces

30
Q

where is the centre of mass for a uniform object?

A

the centre of the object

31
Q

what is the area under a velocity-time graph?

A

displacement travelled

32
Q

what is the area under an acceleration-time graph?

A

velocity

33
Q

as speed increases, air resistance …

A

increases
(proportional to the square of the speed)

34
Q

What is the vertical acceleration in projectile motion?

A

gravitational field strength, g

35
Q

what happens at terminal velocity?

A

the forces acting on the falling object become balanced so the acceleration becomes zero
the object is moving at maximum velocity

36
Q

Is linear momentum conserved only in elastic collisions?

A

no, linear momentum is always conserved

37
Q

what can be described as the rate of change of momentum?

A

force

38
Q

what are two equations for impulse?

A

I = FΔt = Δmv

Physics (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions