Answer:
9 m/s
Explanation:
mass of cannon, M = 100 kg
mass of cannon ball, m = 10 kg
velocity of cannon ball, v = 90 m/s
Let the recoil velocity of cannon is V.
Us ethe conservation of linear momentum, as no external force is acting on the system, so the linear momentum of the system is conserved.
Momentum before the firing = momentum after the firing
M x 0 + m x 0 = M x V + m x v
0 = 100 x V + 10 x 90
V = - 9 m/s
Thus, the recoil velocity of cannon is 9 m/s.
Answer: exotic medium can be engineered to slow light
Explanation:
A parallel circuit - there are multiple branches at which current is able to to be pushed around the circuit.
-- The net effective resistance of 10-ohms and 4-ohms
in series is 14 ohms.
-- The current in the series loop is I = E/R = 42V/14-ohms = 3 amperes.
