Water freezes at zero degrees Celsius (32 degrees Fahrenheit). The solid ice particles absorb heat energy from the warmer air, giving the particles energy and enabling them to move away from one another. ... This is what happens when the ice cube (a solid) turns into water (a liquid)
Answer:
(a)
(b)
Explanation:
<u>For Earth we have:</u>
- mass of earth,
- radius of earth,
- orbital radius,
- period of rotation,
- period of revolution,
(a)
Angular momentum,
∵...............................(1)
For a particle of mass m moving in a circular path at a distance r from the axis,
&
Putting respecstive values in eq. (1)
To model earth as a particle is reasonable because the distance between the sun and the earth is very large s compared to the radius if the earth.
(b)
For a uniform sphere of mass M and radius R and an axis through its center,
using eq. (1)
Answer:
1.25 rev/s
Explanation:
N = mv^2/r (normal force )
f = μN [Frictional force ]
f = mg
μN = mg
μ(mv^2/r) = mg
v = √(rg/μ)
min rotational velocity
v = √(rg/μ) = √(2.5 * 9.8/0.40) = 7.83 rad/sec
= 7.83/2π = 1.25 rev/s
Answer:
662 nm
Explanation:
given,
camera lens of n = 1.5
magnesium fluoride n = 1.38
thickness = 120 n m = 120 × 10⁻⁹m
thickness =
wave length = 120× 10⁻⁹ × 4 × 1.38
= 0.662 × 10⁻⁶ m
= 662 nm
hence, the wavelength is equal to 662 nm
b. seismic waves need a medium for propagation.