Answer:
a) W_total = 8240 J
, b) W₁ / W₂ = 1.1
Explanation:
In this exercise you are asked to calculate the work that is defined by
W = F. dy
As the container is rising and the force is vertical the scalar product is reduced to the algebraic product.
W = F dy = F Δy
let's apply this formula to our case
a) Let's use Newton's second law to calculate the force in the first y = 5 m
F - W = m a
W = mg
F = m (a + g)
F = 80 (1 + 9.8)
F = 864 N
The work of this force we will call it W1
We look for the force for the final 5 m, since the speed is constant the force must be equal to the weight (a = 0)
F₂ - W = 0
F₂ = W
F₂ = 80 9.8
F₂ = 784 N
The work of this fura we will call them W2
The total work is
W_total = W₁ + W₂
W_total = (F + F₂) y
W_total = (864 + 784) 5
W_total = 8240 J
b) To find the relationship between work with relate (W1) and work with constant speed (W2), let's use
W₁ / W₂ = F y / F₂ y
W₁ / W₂ = 864/784
W₁ / W₂ = 1.1
Answer:
Speed of 1.83 m/s and 6.83 m/s
Explanation:
From the principle of conservation of momentum
where m is the mass,
is the initial speed before impact,
and
are velocity of the impacting object after collision and velocity after impact of the originally constant object
Therefore
After collision, kinetic energy doubles hence
Substituting 5 m/s for
then
Also, it’s known that
hence
Solving the equation using quadratic formula where a=2, b=-10 and c=-25 then
Substituting,
Therefore, the blocks move at a speed of 1.83 m/s and 6.83 m/s
I think that the girl has greater tangential acceleration because she is closer to the center and the acceleration is greater there.
Answer:
57.94°
Explanation:
we know that the expression of flux

where Ф= flux
E= electric field
S= surface area
θ = angle between the direction of electric field and normal to the surface.
we have Given Ф= 78 
E=
S=
= 
=0.5306
θ=57.94°
Answer:
Explanation:
Initial velocity u = V₀ in upward direction so it will be negative
u = - V₀
Displacement s = H . It is downwards so it will be positive
Acceleration = g ( positive as it is also downwards )
Using the formula
v² = u² + 2 g s
v² = (- V₀ )² + 2 g H
= V₀² + 2 g H .
v = √ ( V₀² + 2 g H )