Answer:
0.767m
Explanation:
We are given that the time interval between each droplet is equal.
We are also given that the fourth drop is just dripping from the shower when the first hits the floor.
If they fall at the same time interval and we know that the distance between the shower head and floor are the same, they must therefore fall at the same velocity.
The distance between each drop has to be the same given that they fall at equal time intervals.
Let this distance be x.
We can then partition the entire height of the system into three parts (as shown in the diagram).
Hence, we can say that:
x + x + x = 2.3m
3x = 2.3m
=> x = 2.3/3 = 0.767m
Therefore, at the time the first drop hits the floor, the third drop is only 0.767 m below the shower head.
Answer:
Explanation:
Given that,
Emf, V = 22 mV
Number of turns in the coil us 519
Rate of change of current is 10 A/s.
We need to find the magnetic flux through each turn of the coil at an instant when the current is 3.70 A.
Let's find the inductance first. So,
We have,
, 
is magnetic flux
So, the magnetic flux is 
.
Work with your units:
1 watt-hour = 1 (joule/second) · (hour) = 1 (joule-hour / second)
(1 joule-hour/sec) · (3600 sec/hour) = 3600 joules
So 1 watt-hour = 3,600 joules
Objects should be cooled before their mass is determined on a sensitive balance because it could damage the balance. Also, because it would give you wrong reading of the mass. Hot objects would warm the air around it. A warm air would expand and would produce convection as it rises causing to give the object a mass that is less than the actual. Another reason would be it would cause instability in the readings, the mass would fluctuate every now and then due to the convection currents around the object. It is always recommended to weigh the masses of objects that are in room temperature.
