Answer:
Explanation:
Frictional force acting on the box = mg cos 25 x μ where μ is coefficient of friction
= 2.4 x 9.8 x cos 25 x .51 = 10.87 N
Weight of the box acting along the incline = mg sin 25 = 9.94 N
Net force = 10.87 - 9.94 = .93 N . It will create a deceleration of .93 / 2.4
= .3875 m /s² in the box.
v² = u² - 2 a s
v = 0 , a = .3875 , s = 5.4 m
= = u² - 2 x .3875 x 5.4
u = 2.045 m /s
Answer:
Explanation:
Heat required to warm the water from 20 degree to 51 degree
= mct
= 131 x 4150 x ( 51 - 20 )
= 16853150 J
Power of heating element
= v² /R
Heat generated in 31 min
= (v² / r ) x 31 x 60 = 16853150
r = (240 x 240 x 31 x 60) / 16853150
6.35 ohm
In this case heat required will change so time will also change
Heat required =
131 x 4150 x ( 100-51 )
= 26638850 J
If time required be t hour
Energy consumed
Power x time
= (v² / r ) x t x 60 = 26638850
t = 26638850 x 6.35 / (240 x 240 x 60 )
= 48.95 h
Heat required to evaporate water at 100 degree
= mass x latent heat
= 131 x 2260000
= 296060000 J
Total heat required
= 296060000 + 26638850 + 16853150
= 339552000 J
time required = 339552000 x 6.35 / (240 x 240 x 60 )
= 623.88 h .
B) Irregular
Good luck on the rest :D
Answer:
a = 0.009 J
b = 0.19 m/s
c = 0.005 J and 0.004 J
Explanation:
Given that
Mass of the object, m = 0.5 kg
Spring constant of the spring, k = 20 N/m
Amplitude of the motion, A = 3 cm = 0.03 m
Displacement of the system, x = 2 cm = 0.02 m
a
Total energy of the system, E =
E = 1/2 * k * A²
E = 1/2 * 20 * 0.03²
E = 10 * 0.0009
E = 0.009 J
b
E = 1/2 * k * A² = 1/2 * m * v(max)²
1/2 * m * v(max)² = 0.009
1/2 * 0.5 * v(max)² = 0.009
v(max)² = 0.009 * 2/0.5
v(max)² = 0.018 / 0.5
v(max)² = 0.036
v(max) = √0.036
v(max) = 0.19 m/s
c
V = ±√[(k/m) * (A² - x²)]
V = ±√[(20/0.5) * (0.03² - 0.02²)]
V = ±√(40 * 0.0005)
V = ±√0.02
V = ±0.141 m/s
Kinetic Energy, K = 1/2 * m * v²
K = 1/2 * 0.5 * 0.141²
K = 1/4 * 0.02
K = 0.005 J
Potential Energy, P = 1/2 * k * x²
P = 1/2 * 20 * 0.02²
P = 10 * 0.0004
P = 0.004 J
Answer:
False. Field is non-zero
Explanation:
If you were moving along with the electrons, they would appear stationary to you. You would measure a current of zero. However, the fixed positive charges in the wire seem to move backwards relative to you, creating the equivalent current as if you weren't moving. You would measure the same field, but the field would be caused by the 'backward' motion of positive particles.