Answer:
v = 2 v₁ v₂ / (v₁ + v₂)
Explanation:
The body travels the first half of the distance with velocity v₁. The time it takes is:
t₁ = (d/2) / v₁
t₁ = d / (2v₁)
Similarly, the body travels the second half with velocity v₂, so the time is:
t₂ = (d/2) / v₂
t₂ = d / (2v₂)
The average velocity is the total displacement over total time:
v = d / t
v = d / (t₁ + t₂)
v = d / (d / (2v₁) + d / (2v₂))
v = d / (d/2 (1/v₁ + 1/v₂))
v = 2 / (1/v₁ + 1/v₂)
v = 2 / ((v₁ + v₂) / (v₁ v₂))
v = 2 v₁ v₂ / (v₁ + v₂)
Answer:
Surface tension is the tendency of liquid surfaces to shrink into the minimum surface area possible.
Surface tension is caused by effects of intermolecular forces at liquid interface.
Surface tension increases as intermolecular forces increases.
Explanation:
- Surface tension is the tendency of liquid surfaces to shrink into the minimum surface area possible. It can also be seen as the energy required to increase the surface of a liquid by a unit amount.
- Surface tension is caused by the mediating effects of intermolecular forces at the liquid interfaces. Example in water, surface tension is caused by the mediating effect of the force between hydrogen and oxygen molecules. Liquids tends to reduce their surface area because of inward attarction of the liquid molecules.
- Surface tension increases as intermolecular forces increases. Also, surface tension decreases as intermolecular forces decreases.
Answer:
the work that must be done to stop the hoop is 2.662 J
Explanation:
Given;
mass of the hoop, m = 110 kg
speed of the center mass, v = 0.22 m/s
The work that must be done to stop the hoop is equal to the change in the kinetic energy of the hoop;
W = ΔK.E
W = ¹/₂mv²
W = ¹/₂ x 110 x 0.22²
W = 2.662 J
Therefore, the work that must be done to stop the hoop is 2.662 J
Answer:
C) The restoring force
Explanation:
Hooke's Law states that the restoring force acting on a spring is given by the equation:
where
k is the spring constant
x is the displacement of the spring from its equilibrium position
The negative sign in the equation tells the direction of the restoring force. In fact, this force tends to bring the spring back to its equilibrium position: so, the force is always in opposite direction to the displacement.
This means that when the spring is stretched to the right, the restoring force tends to bring it back to the left, to the equibrium position; if the spring is compressed to the left, the restoring force tends to bring it back to the right, to the equilibrium position.
So the correct option is
C) The restoring force
