Answer:
Ac = v²/r
where, Ac is centripetal acceleration
v is velocity
r is radius
5 = (20)²/r
r = 400/5
r = 80m
from,
w = 2πf
where, w = angular velocity and f frequency
w = v/r
f = n/T
then,
v = <u>2πrn</u><u> </u>,n = 1 to complete 1 cycle
T
T = 2πr/v
T = 2π*80/20
T = 25.14seconds.
The car would take 25.14s to complete 1 cycle of the roundabout.
Answer:
Potential energy is energy that is stored in a person or object.Gravitational potential energy depends on an object's weight and its height above the ground (GPE = weight x height). Elastic potential energy is due to an object's shape. It results when an elastic object is stretched or compressed.
Explanation:
Period: Time it takes to complete a cycle, it takes 0.5s to complete a cycle
Frequency: Number of cycles in a second. Since 0.5s = 1 cycle, 1s=2 cycles
Period is 0.5s, frequency is 2
Answer:
a)6.34 x W/m²
b)1.37 x W/m²
c) see explanation.
Explanation:
a)The relation of intensity'I' of the radiation and area 'A' is given by:
I= P/A
where P= power of sunlight i.e 3.9 x J
and the area of the sun is given by,
A= 4π => 4π
A=6.15 x m²
= 3.9 x / 6.15 x =><u> 6.34 x </u><u>W/m²</u>
b) First determine the are of the sphere in order to determine intensity at the surface of the virtual space
A= 4π
Now R= 1.5 x m
A= 4π x 1.5 x =>2.83 x m²
The power that each square meter of Earths surface receives
= 3.9 x /2.83 x =><u>1.37 x </u><u> W/m²</u>
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c) in part (b), by assuming the shape of the wavefront of the light emitted by the Sun is a spherical shape so each point has the same distance from the source i.e sun on the wavefront.