Answer:
a) 2457J
b) 558W
c) 337N
Explanation:
Assuming dogs started from rest.
and the displacement is given by:
Using the energy conservation formula:
Because the motion started from rest the initial kinetic energy is zero, the motion occurred in-ground level so the gravitational energy is zero too.
the work done by the friction force is given by:
so:
The power is given by:
and the force exerted by the dogs:
So many thinks the water wouldnt have as many waves it could result in no season and even an ice age. Nights would be darker. In result in the tides changing animals will be confused, some species rely on the tides for food and shelter. So without that it would cause a chain of mass extinction.
Refraction is the bending of a wave when it enters a medium where its speed is different. This phenomenon is explained by the conservation of energy and conservation of momentum.
Law of Conservation of energy states the total energy of an isolated system remains constant.
law of conservation of momentum states that in a closed system the total momentum is constant.
<span>In refraction, when a medium changes, the phase velocity also changes but its frequency does not; it remains constant. </span>
Answer:
7.1 J
Explanation:
From the question,
Work done by the mover = work done in pushing the crate + work done against friction
W = W'+Wf................. Equation 1
W = mgd+mgμd............ Equation 2
W = mgd(1+μ)................ Equation 3
Where m = mass of the crate, g = acceleration due to gravity, d = distance, μ = coefficient of friction.
Given: m = 46 kg, d = 10.5 mm = 0.0105 m, μ = 0.5
constant: g = 9.8 m/s²
Substitute these values into equation 3
W = 46×9.8×0.0105(1+0.5)
W = 7.1 J
Q3. (a) 0m/s, as they are asking for initial velocit.
(b)(i) The paper has a large surface area or weighs less than the coin,thus,falls smoothly.
(ii)The coin has more mass than the paper.
(c) They fall at the same acceleration and hit the bottom at the same time.
Their mass doesn't matter in the vacuum.
