Mechanics

Question 1

A student is travelling forwards on a skateboard at a constant speed then jumps forwards of it
Explain how NL motion apply
(baseline answer)

Answer 1

Student applies force on skateboard
By N3 the skateboard also applies a force to the student
The two forces are equal in size and opposite in direction
Student accelerates according to N2
Skateboard decelerates according to N2
Skateboard has higher magnitude of acceleration than the student as it has a smaller mass

Question 2

Always remember when answering projectile questions

Answer 2

Split into vertical and horizontal components of velocity
Horizontal component constant

Question 3

Rules for equilibrium

Answer 3

Sum of anti-clockwise moments= sum of clockwise moments
Resultant vertical force must be 0

Question 4

F=mv-mu/t wordy

Answer 4

Talk about rate of change of momentum