1.2 FORCES, ENERGY AND POWER

Question 1

NEWTON’S 1ST LAW

Answer 1

An object will remain at rest or travel in a straight line at a constant velocity if the forces are balanced

TRUST=FRICTION, W=R

Question 2

Second law

UNBALANCED FORCE

or resultant force

Answer 2

Trust-Friction

Fun=R-W (LIFTS), F=ma

Question 3

LIFT HAS UPWARD ACCELERATION OR DOWNWARD SLOWING DOWN

Answer 3

TENSION OF THE CABLE=mg+ma

Question 4

LIFT has DOWNWARDS ACCELERATION or UPWARDS SLOWING DOWN

Answer 4

TENSIONof the cable= mg-ma

Question 5

NEWTON’S 3RD OF LAW OF Motion

Answer 5

If an object exert A a force (the action) on object B,m then object B will exert an equal, but opposite force ( the reaction) on object A

Question 6

Newnton is

Answer 6

Jm

Question 7

The component of the weight parallel to the slope

Answer 7

Wp= mgsinA

Question 8

The component of weight perpendicular to the slope

Answer 8

R= mgcosA

Question 9

Conversation of Energy

in jouls

Answer 9

Energy cannot be created or destroyed, only converted from one form to another

Question 10

Work done

Answer 10

Ew=Fd

Question 11

Potential energy

at particular height

Answer 11

Ep=mgh

Question 12

Power

Answer 12

Watt
P=E/t

Question 13

The work done against friction

Answer 13

Ep-Ek