Answer:
Acceleration of gravity=
Explanation:
Newton's Second Law-acceleration is proportional to the net force acting on an object.
All objects usually free fall at the same acceleration of -this regardless of their mass. This acceleration is known as acceleration of gravity.
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
Answer:
37.42 m/s
Explanation:
We know that apparent frequency, 
is given by
where f is the given frequency in this case 392, V is the speed of sound in air which is given as 343 and 
is the speed of car which is unknown, \bar f is given as 440 Hz
Answer:
Explanation:
E₀ = 229.1 V/m
E = E₀ / √2 = 229.1 / 1.414 = 162 V/m
B = E / c ( c is velocity of em waves )
= 162 / (3 x 10⁸) = 54 x 10⁻⁸ T
rate of energy flow = ( E x B ) / μ₀
= 162 x 54 x 10⁻⁸ / 4π x 10⁻⁷
= 69.65 W per m².
