- Messages
- 381
- Reaction score
- 140
- Points
- 53
S11 qp11
#14
this one is tricky, utilize the kinematics equation
V^2 = U^2 + 2as
so the first drop is
u^2 = 0 + 2ah
the rebound is
0 = v^2 - 2a(h/2) = v^2 - ah
so v^2/u^2 = 1/2
v/u = 1/squareroot 2
#34
R= pl/A
and unit of l/A = m^-1 = V^(-1/3)
so R = p/(V^1/3)
#35
ratio of resistance is 1:2:5 and we know that ratio is current is inverse of that
so must be 1:1/2:1/5 = 10:5:2
so 5x 5/17 = 1.47 answer is C
tyvm, but i still dont understand Q.35, is there an easier way ( i dont know how to find the inverse of a ratio)