Sneajy Things To Remember g

Question 1

How to find sin thetas DONT LACK

Answer 1

We have 3 distances so we MUST use cosine rule
- now here need to remember fact that sin theta = cos (90- theta), and VICE VERCA

Hence find cosine rule to find angle which is cos 90- theta and thst IS SIN THETA

CRAZYYYY

Question 2

Remember when does VELOCOTY change, and when does it reverse ( NOT THE SAME)

Answer 2

Velocity reverse when sign changes
Velocity changes when =0 and sign changes !

When velocity 0 it’s technically NOT THE SAME DIRECTION AS BEFORE

Question 3

Question might ask what driving force can be if something is to decelerate , with a reistance acting

What is the answer

Answer 3

Basicslly the driving force has ti be greater than0 (not 0 because there must be some force )

Now if the driving force tended towards resistance forces, then the distance achieved would go to infinity as decerlwtioj would be SO SMALL

If don’t kniw, find point at which driving force can’t be and set it to that and find limits, you’ll see it goes to infinity

Question 4

Magnitude of contact force, what does this contact force include?

Will there ever be a wacky direction reaction ?

Answer 4

ALL FORCES AT THAT POIMT DUE TO CONTACT = NORMAL AND FRICTION!

2) no, unless stated in question, else always normal and friction, and togther these make CONTACT