Answer: Gravity is the force that keeps planets in orbit around the Sun. Gravity alone holds us to Earth's surface.
Planets have measurable properties, such as size, mass, density, and composition. A planet's size and mass determines its gravitational pull.
A planet's mass and size determines how strong its gravitational pull is.
Models can help us experiment with the motions of objects in space, which are determined by the gravitational pull between them.
Explanation:
Answer:
solution given:
acceleration (a)=?
initial velocity (u)=3m/s
final velocity (v)=6m/s
distance (s)=90m
we have
v²=u²+2as
substituting value
6²=3²+2*a*90
36=9+180a
36-9=180a
a=25/180
<u>a=0.1388m/s²</u>
Answer:
A. The wavelengths of the new sound waves are longer
Explanation:
This is the Doppler effect which can be best illustraded for the case of a siren of an ambulance approaching us having a greater frequency and getting lower in frequency and deeper as the ambulance passes us.
Since the wavelength is inversely proportional to the frequency it follows the wavelengths are longer when the frequency decreases lowering its pitch and getting deeper.
Answer:
Explanation:
We shall apply Stefan's formula
E = AσT⁴
When T = 300
I₁ = Aσ x 300⁴
When T = 400K
I₂ = Aσ x 400⁴
I₂ / I₁ = 400⁴ / 300⁴
= 256 / 81
= 3.16
I₂ = 3.16 I₁ .
Humid air has higher pressure because of the heaviness of the water
