Answer:
4.02 km/hr
Explanation:
5 km/hr = 1.39 m/s
The swimmer's speed relative to the ground must have the same direction as line AC.
The vertical component of the velocity is:
uᵧ = us cos 45
uᵧ = √2/2 us
The horizontal component of the velocity is:
uₓ = 1.39 − us sin 45
uₓ = 1.39 − √2/2 us
Writing a proportion:
uₓ / uᵧ = 121 / 159
(1.39 − √2/2 us) / (√2/2 us) = 121 / 159
Cross multiply and solve:
159 (1.39 − √2/2 us) = 121 (√2/2 us)
220.8 − 79.5√2 us = 60.5√2 us
220.8 = 140√2 us
us = 1.115
The swimmer's speed is 1.115 m/s, or 4.02 km/hr.
We have: a = v/t
Here, t = 2 s [ Given ]
a = 9.8 m/s² [constant value for earth system ]
Substitute their values into the expression:
9.8 = v/2
v = 9.8 × 2
v = 19.6 m/s
In short, Your Answer would be Option B
Hope this helps!
Answer:
D. Exothermic, because energy is being absorbed from the surroundings
Explanation:
This is true about the Exothemic reaction due to the fact that, the reaction occurs outside the body. During this reaction, the energy being absorbed <em>from the surrounding environment will hit the body surface thereby creating the coldness due to the heat given out from the body being minimal.</em>
Answer:
M g H = 1/2 M v^2 potential energy = kinetic energy
v^2 = 2 g H = 2 * 9.80 * 6 = 117.6 m/s^2
v = 10.8 m/s
(C)
