An electric current flows when electrons move through a conductor, such as a metal wire. The moving electrons can collide with the ions in the metal. This makes it more difficult for the current to flow, and causes resistance.
Answer:
b. The final temperature of the coffee cup will be higher than 25°C but less than 75°C.
Explanation:
We know in thermal equilibrium.
Heat loss by one object = Heat gain by other object.
Now, heat is loss by the object whose temperature is higher than other because heat travels from high temperature to other.
And the object who gain heat its temperature increases till both body reach same temperature.
In this case, water loss heat, therefore its temperature decreases.
Similarly , metal block is at low temperature so its temperature increases.
Therefore , both water and metal block must have temperature less than and to have thermal equilibrium.
Answer:
C
Explanation:
The order is this: Displacement --> Velocity --> Acceleration. The velocity directly affects the displacement and the acceleration directly affects the velocity. (changing the acceleration changes the velocity which also changes the displacement).
To go forward in our order, find the slope of the curve/line. To go backwards, find the area under the curve/line. In this case, we are trying to find the displacement of the object, so we should find the area of a velocity-time graph.
Answer:
346.01 × 10² Lux
Explanation:
Given:
luminance of the sun at zenith at sea level, Ls = 1600 × 10 cd/m²
The diameter of the sun's photosphere = 8.64 × 10 miles = 45.62 × 10⁸ ft
or
Radius, r =
or
r = 22.81 × 10⁸ ft
The distance from the sun to the earth = 92.9 × 10 miles = 49.05 x 10¹⁰ ft
Now,
Lumen = Luminance × 4πr²
or
Lumen = 1600 × 10 cd/m² × 4πr² .....................(1)
also,
Illumination =
on substituting lumen from 1
Illumination =
or
Illumination =
or
Illumination = 346.01 × 10² Lux
Answer:
trick question u said bullet and rocket
Explanation: