Answer:
Both AC and DC describe types of current flow in a circuit. In direct current (DC), the electric charge (current) only flows in one direction. Electric charge in alternating current (AC), on the other hand, changes direction periodically.
Answer:
B) 1.5 m/s
Explanation:
The apparent frequency will be enhanced due to Doppler effect
If f be the apparent frequency , F be the real frequency , V be the velocity of sound and v be the velocity of approaching submarine then f is given by
f = F \frac{V+v}{V-v}\\
\frac{f}{F} =\frac{V+v}{V-v}\\
\frac{f}{F}-1 =\frac{V+v}{V-v}-1\\
\Delta f = \frac{2vf}{V-v}\\
200=\frac{2\times v\times 100\times 1000}{1482-v}\\
v=1.48 m/s
Answer:
a) Yes
b) 7 rad/s
c) 0.01034 J
Explanation:
a)
Yes the angular momentum of the block is conserved since the net torque on the block is zero.
b)
m = mass of the block = 0.0250 kg
w₀ = initial angular speed before puling the cord = 1.75 rad/s
r₀ = initial radius before puling the cord = 0.3 m
w = final angular speed after puling the cord = ?
r = final radius after puling the cord = 0.15 m
Using conservation of angular momentum
m r₀² w₀ = m r² w
r₀² w₀ = r² w
(0.3)² (1.75) = (0.15)² w
w = 7 rad/s
c)
Change in kinetic energy is given as
ΔKE = (0.5) (m r² w² - m r₀² w₀²)
ΔKE = (0.5) ((0.025) (0.15)² (7)² - (0.025) (0.3)² (1.75)²)
ΔKE = 0.01034 J
Answer
According to prevailing gender stereotypes most important characteristics associated with men and woman are as follows
1. Domestic behaviors is one of the basic stereotypes. Some people have thinking that women will cook for family, she will take care of the children, she will do loundary and will clean the house. About man they thought he will take care of finances, will pay the bills and do the home repairs.
2. Some people thought that women are emotional and submissive, while men are thought to be self-confident and aggressive.
3.Some people thought that the most common occupation for women are teaching and nursing while the rest of the occupation are for men like pilots, doctors, and engineers are men.
4. Men are expected to be tall and strong while women are expected to be thin and graceful, while.
5. Dressing of men and women also thought to be different. Usually men expected to wear pants and short hairstyles whele women are expected to wear goun, frouks and make-up.
Answer:
4.44 i + 11.11 j , 11.96 m/s
Explanation:
m1 = 0.2 kg, v1 = 10 m/s along X axis, v1 = 10 i
m2 = 0.25 kg, v2 = 20 m/s along north, v2 = 20 j
After collision they stick together and let they move with velocity v.
Use the conservation of momentum
m1 x v1 + m2 x v2 = (m1 + m2) x v
0.2 x (10 i) + 0.25 x (20 j) = (0.2 + 0.25) x v
2i + 5j = 0.45 v
v = 4.44 i + 11.11 j
magnitude of velocity = 
= 11.96 m/s
Thus, the velocity of 0.250 kg hockey puck is 4.44 i + 11.11 j metre per second and the magnitude of velocity is 11.96 m/s.
