Answer:
1703.24J
Explanation:
Given parameters:
Mass of brick = 7.9kg
Height of building = 22m
Unknown:
Potential energy of the brick = ?
Solution:
The potential energy of a body is the energy at rest of the body. Mathematically;
P.E = mgh
m is the mass of the brick
g is the acceleration due to gravity
h is the height of the building
Insert the given parameters and solve;
P.E = 7.9 x 9.8 x 22 = 1703.24J
The so-called "terminal velocity" is the fastest that something can fall
through a fluid. Even though there's a constant force pulling it through,
the friction or resistance of plowing through the surrounding substance
gets bigger as the speed grows, so there's some speed where the resistance
is equal to the pulling force, and then the falling object can't go any faster.
A few examples:
-- the terminal velocity of a sky-diver falling through air,
-- the terminal velocity of a pecan falling through honey,
-- the terminal velocity of a stone falling through water.
It's not possible to say that "the terminal velocity is ----- miles per hour".
If any of these things changes, then the terminal velocity changes too:
-- weight of the falling object
-- shape of the object
-- surface texture (smoothness) of the object
-- density of the surrounding fluid
-- viscosity of the surrounding fluid .
<h2>
Option 1 is the correct answer.</h2>
Explanation:
Power of heater, P = 1790 W
Time used, t = 24 hours = 24 x 60 x 60 = 24 x 3600 s
We have the equation

We need to find energy,
Substituting

Energy = 1790 x 24 x 3600 J
Option 1 is the correct answer.
Answer:
Energy stored, U = 66.6 J
Explanation:
It is given that,
Number of turns in the solenoid, n = 500
Radius of solenoid, r = 1.5 cm = 0.015 m
Distance, d = 15 cm = 0.15 m
Let U is the energy stored in the solenoid. Its formula is given by :

L is the self inductance of the solenoid

N is the no of turns per unit length


L = 0.00148 Henry

U = 66.6 J
Out of given options, the correct option for the energy stored in the solenoid is 70 J. So, the correct option is (a) "70 J".