I think it's 3. within an outer arm
Answer:
1.35208 m/s
Explanation:
Speed of the boat = 0.75 m/s
Distance between the shores = 100 m
Time = Distance / Speed

Time taken by the boat to get across is 133.33 seconds
Point C is 150 m from B
Speed = Distance / Time

Velocity of the water is 1.125 m/s
From Pythagoras theorem

So, the man's velocity relative to the shore is 1.35208 m/s
Answer:
0.31 m
Explanation:
m = mass of the block = 1.5 kg
H = height from which the block is released on ramp = 0.81 m
k = spring constant of the spring = 250 N/m
x = maximum compression of the spring
using conservation of energy
Spring potential energy gained by spring = Potential energy lost by block
(0.5) k x² = mgH
(0.5) (250) x² = (1.5) (9.8) (0.81)
x = 0.31 m
Gravitational potential energy can be calculated using the formula <span>PE = m × g × h, where g is the gravitational acceleration and is constant hence the energy is dependent directly to mass and the height of the object. Hence more PE is registered when the object is heavier and/or at greater initial height. </span>