Answer:
a) 25.5°(south of east)
b) 119 s
c) 238 m
Explanation:
solution:
we have river speed 
=2 m/s
velocity of motorboat relative to water is 
=4.2 m/s
so speed will be:
a) 
=+
solving graphically
=4.7 m/s
Ф=
=25.5°(south of east)
b) time to cross the river: t=
=
=119 s
c) d=
=(2)(119)=238 m
note :
pic is attached
Answer:
v = 344.1 m / s
d = 1720.5 m
Explanation:
For this problem we must calculate the speed of sound in air at 22ºC
v = 331 RA (1+ T / 273)
we calculate
v = 331 RA (1 + 22/273)
v = 344.1 m / s
the speed of the wave is constant,
v = d / t
d = v t
we calculate
d = 344.1 5
d = 1720.5 m
B.strong but weaker than the weak force
There are no rules that can be used to answer that question.
Some of the main reasons include:
-- There's no such thing as the force of energy.
and
-- There's no such thing as negative force.
and
-- The phrase "continuum of movement" is rather vague.
Otherwise, the question is quite intriguing.
Displacement/Time = 21m / 15s .
That's choice-D .
