Answer:
40m
Explanation:
let's calculate the acceleration first
force = mass × acceleration
rearranging to find acceleration:
acceleration = force ÷ mass
force = 25N, mass = 5.0kg
acceleration = 25 ÷ 5 = 5ms^-2
we can now use the formula v^2 = u^2 + 2as where v = final velocity, u = initial velocity, a = acceleration and s = distance
rearranging v^2 = u^2 + 2as the distance is
s = (v^2 - u^2) ÷ 2a
v = 20, u = 0, a = 5
s = (20^2 - 0^2) ÷ (2 × 5) = 40m
the distance is 40m
Answer:
Explanation:
(ΔK + ΔUg + ΔUs + ΔEch + ΔEth = W)
ΔK is increase in kinetic energy . As the athelete is lifting the barbell at constant speed change in kinetic energy is zero .
ΔK = 0
ΔUg is change in potential energy . It will be positive as weight is being lifted so its potential energy is increasing .
ΔUg = positive
ΔUs is change in the potential energy of sportsperson . It is zero since there is no change in the height of athlete .
ΔUs = 0
ΔEth is change in the energy of earth . Here earth is doing negative work . It is so because it is exerting force downwards and displacement is upwards . Hence it is doing negative work . Hence
ΔEth = negative .
b )
work done by athlete
= 400 x 2 = 800 J
energy output = 800 J
c )
It is 25% of metabolic energy output of his body
so metalic energy output of body
= 4x 800 J .
3200 J
power = energy output / time
= 3200 / 1.6
= 2000 W .
d )
1 ) Since he is doing same amount of work , his metabolic energy output is same as that in earlier case .
2 ) Since he is doing the same exercise in less time so his power is increased . Hence in the second day his power is more .
Answer:
The metric system is the official system for all nations of the world.
Explanation:
To make measures, it is necessary to have a set of standardized magnitudes to compare things we want to measure. This set of standardized magnitudes is called a unit system.
The metric system is a decimalized system of measurement which has meters and grams as a basic measurement unit. The metric system is the most used in the world, and also, is the official system for all nations of the world.
Answer:
Though nepalgunj and taplegunj lie at the same latitude(28 degree) they greatly vary In climate..