AS mechanics

Question 1

how many kg in a tonne

Answer 1

1000 kg = 1 tonne

Question 2

how many mg in a gram

Answer 2

1000 mg = 1g

Question 3

how many nano metres in a metre

Answer 3

1 x 10^9 nano metres

Question 4

what are the main units used in mechanics for:
- length
- time
- mass

Answer 4

• metres
• seconds
• kg

Question 5

are the following quantities scalars or vectors :
- mass
- weight

Answer 5

• scalar
• vector, it is a force so it has a direction

Question 6

what is acceleration measured in

Answer 6

metres per second squared

Question 7

what is force measured in

Answer 7

newtons

Question 8

how do you calculate force

Answer 8

force = mass x acceleration

Question 9

what are derived units

Answer 9

a combination of S I units

Question 10

is force a scalar or vector

Answer 10

• vector, it has a magnitude and direction

Question 11

what is tension

Answer 11

• a pulling force that acts away from the objects

Question 12

what is thrust

Answer 12

• a pushing force that acts towards objects
• also known as compression

Question 13

can a string have the force of thrust acting on it

Answer 13

• no, a string can only every experience tension
• if pushed, a string will go slack

Question 14

what is friction

Answer 14

• a resistive force that acts in the opposite direction to motion
• acts between two touching objects
• e.g. air resistance, water resistance

Question 15

how do you calculate weight

Answer 15

weight = mass x gravity

Question 16

what is the normal reaction force

Answer 16

• the force acting perpendicular to the line of contact between two objects
• ALWAY occurs between two objects

Question 17

what is driving force

Answer 17

• force typically created by an engine that causes the vehicle to accelerate

Question 18

what is braking force

Answer 18

• a resistive force caused by a vehicle, making is decelerate

Question 19

• what is fluid resistance

Answer 19

• a resistive force depending on the viscosity of a fluid
  e.g. swimming through honey instead of water

Question 20

what does it mean when the sum of a particles vector forces are equal to 0

Answer 20

• the particle is in equilibrium

Question 21

how do you find the magnitude of a vector

Answer 21

Pythagoras

Question 22

how do you find the direction of a vector

Answer 22

trigonometry