Physical Quantities and Measuring Techniques

Question 1

measuring cylinder for volume

Answer 1

they are normally used to find the volume of irregular shaped objects, where you use the displaced amount of water, to determine to volume of the object

Question 2

ruler for length

Answer 2

to help you find the length of objects

Question 3

how to measure time intervals

Answer 3

subtract the final value by the initial value

Question 4

how to calculate the period of a pendulum

Answer 4

1 oscillation is the back and forth of a pendulum and the period is the time that the pendulum takes for 1 oscillation and so the pendulum will go to fast, that is why, try to measure the time it takes for the pendulum to oscillate 20 times and divide that time by 20

Question 5

how to measure the thickness of something

Answer 5

if you want to measure a page, then you look at the thickness of the book, see how many pages it has and divide the thickness by the pages

Question 6

stopwatches for time

Answer 6

to measure multiple periods like 20 periods

Question 7

vector quantities

Answer 7

have magnitude and direction (acceleration, velocity, weight, force, gravitational field strength)

Question 8

scalar quantities

Answer 8

only have magnitude/size
(mass, distance, speed, temperature, energy or time)

Question 9

energy stores

Answer 9

• KINETIC ENERGY
• GRAVITATIONAL POTENTIAL
• CHEMICAL
• ELASTIC (STRAIN)
• ELECTRICAL
• HEAT
• LIGHT
• SOUND
• NUCLEAR
• INTERNAL

Question 10

equation for kinetic energy

Answer 10

1/2 x m x v squared

Question 11

equation for gravitational potential energy

Answer 11

mass x gravity x height

Question 12

equation for change in gravitational potential energy

Answer 12

mass x gravity x change in height

Question 13

energy is transferred between different stores, like when it transfers because of mechanical work done

Answer 13

when a force moves an object
like when we put books back in shelves
(chemical energy in muscles transferes to GPE in the shelf.)

Question 14

electrical work done

Answer 14

electric currents (charges flow in a circuit,)
like when we use battery to power toys
(chemical energy in the battery is transferred to kinetic energy in the toy

Question 15

heating

Answer 15

when energy moves from thermal store of warm object to cool object
like when hand warmers warm up your hand (thermal energy in the hand warmer, is transferred by conduction to thermal energy in your hands)

Question 16

radiation

Answer 16

when energy is transferred as waves, such as heat, sound or light
like radiation form a toaster
(thermal energy of the grill is transferred to thermal energy in the food)

Question 17

energy transfer when ball drops

Answer 17

total energy before = total energy after
(when a ball drops and falls to the ground, when it is at the top, the kinetic energy is at zero but the GPE is at its maximum, and just before it hits the ground, the GPE is at zero, but the KE is at its maximum

Question 18

energy cant be..

Answer 18

created, it cant be destroyed, it can only be transferred

Question 19

the sun

Answer 19

nuclear –> light and heat

Question 20

a phone

Answer 20

chemical –> light, sound and heat

Question 21

catapult

Answer 21

elastic –> GPE and kinetic

Question 22

burning match

Answer 22

chemical + heat + light