phys 🔬⚗️

Question 1

what formula is used to calculate speed?

Answer 1

Speed= Distance/time

Question 2

how do you calculate average speed

Answer 2

Total distance/Total time taken (Because speed is not always constant throughout the journey)

Question 3

Difference between speed and velocity

Answer 3

Speed simply the rate at which an object covers a distance (scalar)

While Velocity measures speed in a specific direction. (vector)

Question 4

What does a minus or plus sign mean with velocity

Answer 4

• = Going the opposite direction
  + = moving in the positive direction. (right or up or left or down depends on the context)

Question 5

What does a straight line on a DT graph mean

Answer 5

That the object has paused

Question 6

What does a curve mean on a DT graph

Answer 6

acceleration

Question 7

what does diagonal straight incline mean on DT

Answer 7

Constant speed

Question 8

What is acceleration

Answer 8

Acceleration is the rate at which an object’s velocity changes over time.

Question 9

How is acceleration shown on a DT graph

Answer 9

A smooth curve

Question 10

how can acceleration be calculated

Answer 10

change in velocity/time taken

Question 11

Horizontal line on a VT graph

Answer 11

steady speed

Question 12

Straight diagonal line on a VT graph

Answer 12

steady acceleration

Question 13

Curve on a VT graph

Answer 13

A curve on a VT graph indicates changing acceleration

Question 14

How do you find distance from a VT graph

Answer 14

The area under a VT graph gives the distance because Distance =speed x time

(make sure unit is consistent)

Question 15

What happens when you drop an object

Answer 15

Gravity acts on the object and causes it to accelerate.

This acceleration of free fall g is constant for a body near the earth, acts downwards and has a value of approximately 9.8m/s^2

Question 15

unit for acceleration

Answer 15

m/s^2

Question 16

How can you tell from a distance time graph whether the object is moving away from you or toward you?

Answer 16

If the distance is increasing (the graph slopes upward), the object is moving away from you.

If the distance is decreasing (the graph slopes downward), the object is moving toward you.

Question 17

Acceleration

Answer 17

The rate (how quickly) of change of velocity.

Question 18

Acceleration formula

Answer 18

change in velocity/ time taken

a= (v-u)/t

v= final velocity in m/s
u= starting velocity in m/s
t= time taken s

Question 19

calculate the acceleration of a car that travels from 0m/s to 28 m/s in 10 seconds

Answer 19

2.8m/s^2

Question 20

As a stone falls it accelerates from 0m/s to 20m/s in 2 seconds. calculate its acceleration and state unit.

Answer 20

10m/s^2

Question 21

A racing car slows down from 45m/s to 0 m/s in 3 seconds. Calculate the acceleration

Answer 21

-15m/s^2- final velocity=0 - initial velocity 45 -45/3= -15

Question 22

How do you calculate acceleration from a speed time graph

Answer 22

the gradient of a speed-time graph

Question 23

How do you find distance from a speed-time graph

Answer 23

the area beneath the graph

always make sure the units are consistent

Question 24

Two runners complete a 400m race. Athlete A takes 50s and athlete B takes 64s calculate the average speed of each runner

Answer 24

8m/s and 6.25 m/s

Question 25

What is the vector version of these: -speed -distance

Answer 25

-velocity -displacement

Question 26

What does a steep slope on a distance-time graph represent?

Answer 26

The object is moving quickly. The steeper the slope, the faster the object is moving.

Question 27

How can you determine the speed of an object from a distance-time graph?

Answer 27

Speed is the gradient (slope) of the line. A steeper slope means a higher speed.

Question 28

What does a curved line on a distance-time graph mean about the object’s motion?

Answer 28

The object’s speed is changing, meaning it's either accelerating or decelerating.

Question 29

What does a horizontal line on a velocity-time graph represent?

Answer 29

The object is moving at a constant velocity.

Question 30

What does a negative slope on a velocity-time graph suggest?

Answer 30

The object is decelerating (slowing down).

Question 31

What does a horizontal line on a velocity-time graph represent?

Answer 31

The object is moving at a constant velocity.

Question 32

Mass (scalar)

Answer 32

How much material is present in the object (g,kg etc.)

Question 33

Weight (vector)

Answer 33

force on the object due to gravity (N)

Question 34

velocity

Answer 34

rate of change of displacement (distance travelled) (m/s)

Question 35

Weight formula

Answer 35

m (mass) x g (gravitational field strength)

Question 36

gravitational field on earth

Answer 36

9.8

Question 37

mass is a property that _____ change in motion

Answer 37

resists

Question 38

how do you find the mass of something?

Answer 38

The most accurate way is with a balance. The balance is level when the forces pulling down both sides are the same.

Question 39

How do you find the weight of something?

Answer 39

A spring balance: -The top of the spring is hung from a hook -The scale can then be adjusted so that the pointer is aligned

Question 40

Gravity is an _____ , _______ force

Answer 40

attractive, non contact

Question 41

What is gravitational force

Answer 41

acceleration due to gravity

Question 42

why does a heavier object fall faster than a lighter object

Answer 42

due to air resistance or water resistance

Question 43

Terminal velocity

Answer 43

The constant speed that a falling object reaches because the force of gravity is balanced by air resistance.

Question 44

field strength

Answer 44

N/kg

Question 45

what is density

Answer 45

how much mass is in 1m^3 or 1cm^3 of an object

Question 46

formula for density

Answer 46

ρ=m/v. mass/volume.

Question 47

density of water

Answer 47

1g/cm^3

Question 48

what happens when the density of an object is less than the fluid

Answer 48

it floats

Question 49

what happens when the density of an object is more than the fluid

Answer 49

it sinks- upthrust is less than weight

Question 50

what happens when objects fall in a vacuum

Answer 50

there is no air resistance or liquid resistance so the only force acting on them is the force of weight.

Question 51

what is a vacuum

Answer 51

a space that contains no matter

Question 52

force formula

Answer 52

mass x acceleration

Question 53

What is upthrust

Answer 53

the force that pushes upwards on an object submerged in a liquid.

Question 54

what direction does upthrust always act in

Answer 54

opposite direction to the object's weight force

Question 55

The ________ the object the _________ the upthrust

Answer 55

denser greater

Question 56

what does an object floating say about the upthrust

Answer 56

it is equal to the weight.

Question 57

what does the size of upthrust depend on

Answer 57

the density of the fluid The volume of fluid pushed aside (equal to the volume of the object)

Question 58

how do you calculate the density of a regularly shaped object

Answer 58

1. Measure the mass: Use a balance or scale to find the object's mass in kilograms (kg) or grams (g). 2. Find volume by finding length, width, height mass/volume

Question 59

how do you calculate the density of an irregularly shaped object

Answer 59

1. measure mass 2. measure volume- measure the original volume of water then 3. submerge the object in the water completely, ensuring it’s fully underwater 4.Measure the new water level. The increase in water level shows the volume of the object. Final water level - Initial water level 5. mass/volume

Question 60

what can be certain flaws in calculating the density of an irregularly shaped object

Answer 60

-The water level may not be read accurately. -The object might not be fully submerged, leading to incorrect displacement.

Question 61

what does resultant force= 0 look like on a vt graph

Answer 61

horizontal line- acceleration=0