A. Coming out near the South Pole and going in near the North Pole
The springs stored energy is transferred to the cube as kinetic energy and then by the slop the KE is converted to height energy.
<span>0.5 . k . x^2 = 0.5 . m . v^2 = m . g . ∆h </span>
<span>0.5 . 50 . (0.1^2) = 0.05 . 9.8 . ∆h </span>
<span>∆h = 0.51 m = 51 cm </span>
<span>This is the height gained </span>
<span>Distance along the slope = ∆h / sin 60 = 0.589 = 59 cm </span>
<span>In the second case, the stored spring energy is converted into height energy AND frictional heat energy. </span>
<span>The height energy is m . g . d sin 60 where d is the distance the cube moves along the slope. </span>
<span>The Frictional energy converted is F . d </span>
<span>F ( the frictional force ) = µ . N </span>
<span>N ( the reaction to the component of the gravity force perpendicular to the surface of the slope ) = m . g . cos60 </span>
<span>Total energy converted </span>
<span>0.5 . k . x^2 = (m . g . dsin60) + (µ . m . g . cos60 . d ) </span>
<span>Solve for d </span>
<span>d = 0.528 = 53 cm</span>
<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.
Answer:
We see objects in a dark room due to the emission of light photons which are sensitive to our eyes. Darkness is simply a terminology used to describe the absence of light. Visible light to human is a component of the electromagnetic spectrum. Our eyes have receptors that picks the photons which light releases
Explanation:
