Answer:
A) the current in AC electricity varies in magnitude and direction.
C) the voltage in AC electricity varies in magnitude and direction.
Explanation:
In DC current and voltage the direction of current will not change with time and it always remains the same.
So here in DC voltage and DC current the magnitude may change with time but the direction will always remain same
While in AC voltage and AC current the direction of AC will change with time
periodically.
So here magnitude and direction both will change in AC current and AC voltage.
so the correct answer is
A) the current in AC electricity varies in magnitude and direction.
C) the voltage in AC electricity varies in magnitude and direction.
The right formula to use for this calculation is the heat capacity formula,
Heat absorbed, Q = MCT, Where
M = Mass of the substance = 71
C = Specific heat capacity for iron = 0.450 J/gc
T = Change in temperature = 29 - 11 = 18
Q = 71 * 0.450 *18 = 575.10
The amount of heat absorbed by the iron skillet is 575 J.
Answer:
Explanation:
a ) work done by gravitational force
= mg sinθ ( d + .21)
Potential energy stored in compressed spring
= 1/2 k x²
= .5 x 431 x ( .21 )²
= 9.5
According to conservation of energy
mg sinθ ( d + .21) = 9.5
3.2 x 9.8 x sin 30( d + .21 ) = 9.5
d = 40 cm
b )
As long as mg sin30 is greater than kx ( restoring force ) , there will be acceleration in the block.
mg sin30 = kx
3.2 x 9.8 x .5 = 431 x
x = 3.63 cm
When there is compression of 3.63 cm in the spring , block will have maximum velocity. there after its speed will start decreasing.
Answer:
h = 90.10 m
Explanation:
Given that,
A man is standing near the edge of a cliff 85 meters high, h₀ = 85 m
The initial speed of the stone, u = 10 m/s
The path followed by the projectile is given by :
....(1)
For maximum height,
Put dh/dt = 0
So,
Put the value of t in equation (1).
So, the maximum height of the stone is equal to 90.10 m.
