Answer:
Gold is not used for making electric wires because it is too rare, and too costlier than Copper. Silver and copper are used for making wires. Copper is almost used in electric lines
Answer:
The SI unit of intensity is the watt per square meter/metre (W/m^2.)
Explanation:
Intensity is equal to the power transferred per unit area. Since power is measured in watts (W) and 1 W = 1 J/s, then intensity can be viewed as how fast energy goes through a certain area.
In physics, intensity is often used when studying light, sound, or other phenomena that involve waves or energy transfer. (With waves, the power value is taken as the average power transfer over the wave's period.)
Answer:
Sarah is right
Explanation:
This is an exercise that differentiates between scalars and vectors.
A scalar is a number, instead a vector is a number that represents the module in addition to direction and sense.
In this case, the distance (scalar) traveled is a number, which is why it is worth 1500m, but the displacement is a vector and since the point where it leaves is the same point where the vector's modulus arrives is zero, so the DISPLACEMENT VECTOR is zero
consequently Sarah is right
E=mgh. 196=5kg*9.81m/s^2*h. So h=196/(5*9.81)=4m
