Answer: radiator - A radiator puts warm air out at the top and draws in cooler air at the bottom. steaming cup of hot tea - The steam you see when drinking a cup of hot tea indicates that heat is being transferred into the air. ice melting - Ice melts because heat moves to the ice from the air.
Explanation:
Answer:
C. Both of A and C
Explanation:
Primary colors are colors that can be combined with one another to form other colors called secondary colors.
Light can be defined as a phenomenon that causes the sensation of vision. The primary colors with regards to light are: red, green and blue. Light is a form of an additive system where there is an addition of two or more primary colored lights to form other colors.
Paints are subtractive systems that produce color due to absorption and reflection of colors. A green paint appears green because it has absorbed other colors and reflects only green. Its primary colors are blue, yellow and green.
Therefore, paints reflect light and take out light from what light is shined onto them.
Answer:
<em>
60 V
</em>
<em>
Current will flow anticlockwise from the right side of the magnet.
</em>
Explanation:
The number of turns on the coil = 40 turns
The magnetic flux changes by ∆Φ = 0.3 T.m^2
The time changes by ∆t = 0.2 s
The induced emf can be gotten as
E = N∆Φ/∆t
substituting values, we have
E = (40 x 0.3)/0.2 = <em>60 V
</em>
If we move the magnet away from the coil, then from Lenz law, the induced current on the coil will try to oppose the motion of the magnet by attracting the magnet towards the coil. For this to happen, the coil must possess the equivalent of a magnetic south pole. For the equivalent of a magnetic south pole, the current on the coil will flow in the clockwise direction when viewed from the left side of the magnet. <em>This will appear as an anticlockwise direction, when viewed from the right side of the magnet.</em>
<h2>The intensity at a distance of 4.5 cm is 68.9 N/C</h2>
Explanation:
The electric field intensity on the surface of cylinder E₁ = λ/2πε₀R I
here λ is the charge density of cylinder
R is the radius of cylinder
and 1/2πε₀ is a constant of permitiivity
Similarly the intensity at a distance r from center of cylinder
E₂ = λ/2πε₀r II
Dividing II by I , we have
E₂/E₁ = R/r
here E₁ = 155 N/C
R = 2.0 cm and r = 4.5 cm
Substituting , the value
E₂/155 = 2/4.5
or E₂ = x 155 = 68.9 N/C
( b ) Because E = - dV/dr
Here V is the potential at a point
Thus V = -
Here E = λ/2πε₀r and b = 2cm and a = 4.5 cm
Thus VB - VC = λ/2πε₀ [ log4.5 - log2 ]
( c ) The potential at points A and B is the same .
Thus VA - VB = 0