Speed has the dimensions of distance divided by time. The SI unit of speed is themetre<span> per second, but the most common unit of speed in everyday usage is the kilometre per </span>hour<span> or, in the US and the UK, miles per </span>hour<span>. For air and marine travel the knot is commonly used.</span>
Answer:
(a) -472.305 J
(b) 1 m
Explanation:
(a)
Change in mechanical energy equals change in kinetic energy
Kinetic energy is given by
Initial kinetic energy is
Since he finally comes to rest, final kinetic energy is zero because the final velocity is zero
Change in kinetic energy is given by final kinetic energy- initial kinetic energy hence
0-472.305 J=-472.305 J
(b)
From fundamental kinematic equation
Where v and u are final and initial velocities respectively, a is acceleration, s is distance
Making s the subject we obtain
but a=\mu g hence
... the density of the liquid
... the volume of the submerged object
Answer:
y = 10.44cos(2t - 0.291) cm
Explanation:
y = Acos(2πt/T + φ) = Acos(2πt/π + φ) = Acos(2t + φ)
v = y' = -2Αsin(2t + φ)
10 = Acos(2(0) + φ) = Acosφ
6 = -2Αsin(2(0) + φ) = -2Asinφ
6/10 = -2Asinφ/Acosφ = -2tanφ
tanφ = -0.3
φ = -0.291 radians
10 = Acos(-0.291)
A = 10/cos(-0.291) = 10.44