The Student Room Group
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>
Competition - post a photo you've taken of nature >>

m3 help further kinematics

DSCF2241.jpg

not sure how to work this out. any help please?
Reply 1
Avatar for MK_
MK_
Original post by Cheesegrater4
DSCF2241.jpg

not sure how to work this out. any help please?

Have you done differential equations in C4?
Reply 2
Avatar for Cheesegrater4
Cheesegrater4
OP
7
Original post by MK_
Have you done differential equations in C4?


yes
Reply 3
Avatar for MK_
MK_
Original post by Cheesegrater4
yes

Oops, I misread at first, I thought the problem was with solving the de rather than setting it up. Do you understand where the left hand side comes from? If not, think about acceleration as a differential and then use the chain rule to express it in terms of v and x. Then the right hand side comes from Newton's 2nd Law and realising that 'increases uniformly with the distance moved' means that the resistive force is proportional to the distance travelled.
(edited 10 years ago)
Reply 4
Avatar for Cheesegrater4
Cheesegrater4
OP
7
i get that acceleration = v dv/dx but i don't get what you mean about using newtons second law?
Reply 5
Avatar for MK_
MK_
Original post by Cheesegrater4
i get that acceleration = v dv/dx but i don't get what you mean about using newtons second law?

The net force on the object is equal to mass*acceleration, and you have the acceleration for two values of x.
Original post by Cheesegrater4
i get that acceleration = v dv/dx but i don't get what you mean about using newtons second law?


you don't need Newtons second law. You are told what the acceleration is so just put (v)dv/dx = to that expression.
(edited 10 years ago)

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you