foundations of physics

Question 1

random error

Answer 1

A random error is unpredictable error
affects the gradient of the graph
can reduce the affect by taking more measurements

Question 2

systematic error

Answer 2

affects all data by the same amount
not affect the gradient of the graph however it will displace it

Question 3

absolute uncertainty of a value =

Answer 3

half the range or smallest reading

Question 4

stopping distance consists of

Answer 4

thinking distance= the distance travelled between the moment you see the reason needed to stop and the moment you use the break
** (speed x reaction time) **
breaking distance= distance from the time the break is applied to the time the vehicle stops

Question 5

centre of gravity

Answer 5

an imaginary point at which the entire weight of an object appears to act

Question 6

finding the centre if gravity

Answer 6

make holes in object along card
suspend object in a pin held by a clamp
allow object to swing freely
hang a plumb line from the centre of the pin and draw a line where the string hangs
repeat process for other holes
centre of gravity is the point of intersection of these lines

Question 7

what is friction
tension
upthrust

Answer 7

force that arises when two surfaces rub against each other
force in a stretched cable or rope
upward buoyancy force acting on an object

Question 8

force parallel to slope

Answer 8

mgsin(0)

Question 9

what is a couple
2 conditions for a couple

Answer 9

A pair of equal and opposite forces acting on a body but not in the same straight line
-must be coplanar
- must be equal and opposite in magnitude

Question 10

what is a torque

Answer 10

moment of a couple