Answer:
Explanation:
Area A of the coil = .1 x .1 = .01 m²
no of turns n = 5
magnetic field B = .5 t²
Flux Φ perpendicular to plane passing through it.= nBA sin30
rate of change of flux
dΦ/dt = nAdBsin30 / dt
= nA d/dt (.5t²x .5 )
= nA x 2 x .25 x t
At t = 4s
dΦ/dt = nA x 2
= 5x .01 x 2
= .1
current = induced emf / resistance
= .1 / 4
= .025 A
= 25 mA.
Answer:
B. Steam burns the skin worse than hot water because the latent heat of vaporization is released as well.
Explanation:
It is given that both steam and the boiling water when in contact with the skin cools down from 100 to 34 degrees Celsius.
For any substance of mass m, the heat required to change the temperature by is (S.I. unit = Joules).
where C, the specific heat capacity is the same and a constant for both the condensed steam and the boiling water.
But, there is a "hidden" energy (heat) released by the steam called latent heat
(given by mL, L = specific latent heat) which allows the phase transition (gas to liquid). While both of them are at the same temperature, their energy (heat) is different, which is why steam causes burns worse than boiling water
Answer:
Because it has more mass
Explanation:
To understand this, think about the equation of kinetic energy
KE = m
Kinetic energy depends on both the velocity (v) as well as the mass (m).
Because a lorry is bigger and heavier than a car, it will have more mass. With more mass, at the same velocity the lorry with have more kinetic energy.
The answer is centimeters.
Answer:
Option D
+2
Explanation:
We know that Calcium has 20 electrons and 20 protons. It lost two electrons, it has 20 protons, but only 18 electrons. This makes calcium a positive ion with a charge of +2.