Power (rate of using energy) = (voltage) x (current)
Power of this heating element = (120 V) x (3.2 A) = 384 watts
The easy way:
384 watts = 0.384 kilowatt
(0.384 kilowatt) x (5 hours) = 1.92 kilowatt-hour
Another way:
384 watts = 384 joules per second .
(384 joule/sec) x (3600 sec/hour) x (5 hours)
= (384 x 3600 x 5) (joules) = 6,912,000 joules.
Answer:
C. An external downward field is created or an external downward field is removed
Explanation:
As we can see that from the attached figure that the induced current would be counter clockwise. So the field occur because of induced current i.e. out of page. This represent that the current is induced in order to rise the flux out of the direction of the page
Therefore because of the external field, the field out of page & flux would be reducing or the external upward field is eliminated
So option C is correct
In the conservation of mass, mass is never created or destroyed in chemical reactions in the same way water is not created or destroyed it is only transferred from one form to another and its mass is always conserved.
Answer:
6.86 × 10²⁴ kg
Explanation:
The mass of the earth m = density of earth, ρ × volume of earth, V
m = ρV
The density of the earth, ρ = 5515 kg/m³ and since the earth is a sphere, its volume is the volume of a sphere V = 4πr³/3 where r = radius of the earth = 6.67 × 10⁶ m
Since m = ρV
m = ρ4πr³/3
So, substituting the values of the variables into the equation for the mass of the earth, m, we have
m = 5515 kg/m³ × 4π(6.67 × 10⁶ m)³/3
m = 5515 kg/m³ × 4π × 296.741 × 10¹⁸ m³/3
m = 5515 kg/m³ × 1189.9639π × 10¹⁸ m³/3
m = 6546105.64378π × 10¹⁸ kg/3
m = 20565197.400122 × 10¹⁸ kg/3
m = 6855065.8 × 10¹⁸ kg
m = 6.8550658 × 10²⁴ kg
m ≅ 6.86 × 10²⁴ kg
