Answer:
Part a)

Part b)

Explanation:
As we know that mountain climber is at rest so net force on it must be zero
So we will have force balance in X direction


now we will have force balance in Y direction


Part a)
so from above equations we have



Part b)
Now for tension in right string we will have


Find the horizontal components vcos30 ...one goes right and one goes left so they cancel each other.
Find vertical components vsin30.....there are two of them.... so 2vcos30....hey presto... resultant velocity = 2vCos30
<h2>
Speed of motorboat is 36 km/hr and speed of current is 4 km/hr.</h2>
Explanation:
Let speed of motor boat be m and speed of current be c.
A motorboat traveling with a current can go 160 km in 4 hours.
Distance = 160 km
Time = 4 hours
Speed = m + c
We have
Distance = Speed x Time
160 = (m+c) x 4
m + c = 40 --------------------- eqn 1
Against the current it takes 5 hours to go the same distance.
Distance = 160 km
Time = 5 hours
Speed = m - c
We have
Distance = Speed x Time
160 = (m-c) x 5
m - c = 32 --------------------- eqn 2
eqn 1 + eqn 2
2m = 40 + 32
m = 36 km/hr
Substituting in eqn 1
36 + c = 40
c = 4 km/hr
Speed of motorboat is 36 km/hr and speed of current is 4 km/hr.
<h3><u>Solution</u><u>:</u></h3>
- Distance (d) = 112 m
- Time (t) = 4 seconds
- Let the speed be v.
- We know, speed = Distance / Time
- Therefore, v = d/t
or, v = 112 m ÷ 4 s = 28 m/s
<h3><u>Answer</u><u>:</u></h3>
<u>The </u><u>speed </u><u>of </u><u>the</u><u> </u><u>cheetah</u><u> </u><u>is </u><u>2</u><u>8</u><u> </u><u>m/</u><u>s.</u>