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.
They use Newton to measure force
Answer:
a = -4/5 m/s^2
Explanation:
Acceleration = change in velocity / time
change in velocity = final velocity - initial velocity
a = (20 m/s - 60 m/s) / 50 s
a = -40 m/s / 50 s
a = -4/5 m/s^2
hope this helps! <3
Answer:
mass of an object
Explanation:
because mass of an object changes it’s force