Answer:
speed of current is 5 mile/hr
Explanation:
GIVEN DATA:
speed of motorboat = 15 miles/hr relative with water
let c is speed of current
15-c is speed of boat at upstream
15+c is speed of boat at downstream
we know that
travel time=distance/speed

150+10c+150-10c=1.5(15-c)(15+c)
300=1.5(225-c^2)
300=337.5-1.5c^2
200=225-c^2
c^2=25
c = 5
so speed of current is 5 mile/hr
Answer:
the train is moving at the speed of v = 1.79 m/s
Explanation:
given,
rain drop is falling vertically down with the speed of = 3.84 m/s
angle of the rain drop = 25°
tan θ =
tan 25° =
v =3.84 × tan 25°
v = 1.79 m/s
hence, the train is moving at the speed of v = 1.79 m/s
Momentum = m • v
Original momentum = m • 10 m/s north
Final momentum = m • 15 m/s north
Change = m • (15 - 10) m/s north
Change = m • +5 m/s north
Change = +60 kg-m/s north
17. C. Isotopes
18. Tracers
19. Alpha Decay