The speed is changing its direction all the time. There
is an acceleration which changes the direction of the speed – that is called
centripetal acceleration. Only uniform linear motions are considered to have no
acceleration.
This is the general formula for acceleration
a = dv/dt
When calculating dv, you should keep in mind the change
in the velocity vector’s direction. You can easily see in a graph that with dt
tending to 0 (so the length of the arc covered is also tending to 0), the difference
between vectors Vf and V0 has a direction which is perpendicular to velocity
(the shorter the arc, the closest the angle is to 90 degrees).
There is a formula (which can be deducted from the
previous formula) which allows you to calculate the acceleration:
a = v^2/r
Let’s talk about the units:
v is in m/s
r is in m
so v^2/r
is in (m/s)^2/m = (m^2/s^2)/m = m/s^2
which is the same unit as dv/dt:
dv/dt = (m/s)/s= m/s^2
Answer: A) 
Explanation:
The equation for the moment of inertia 
of a sphere is:
(1)
Where:
is the moment of inertia of the planet (assumed with the shape of a sphere)
is the mass of the planet
is the radius of the planet
Isolating from (1):
(2)
Solving:
(3)
Finally:
Therefore, the correct option is A.
A beat is an interference pattern between two sounds of slightly different frequencies, perceived as a periodic variation in volume whose rate is the difference of the two frequencies. Frequency beat is equal to,
The reference frequency in our case would be 392Hz, and since there is the possibility of the upper and lower range for the amount of beats per second that the two possible frequencies are heard would be
Therefore the two possible frequencies the piano wire is vibrating at, would be 396Hz and 388Hz
Answer:
Explanation:
distance of shuttle from centre of the earth = radius of the orbit
= 6300 + 300 = 6600 km
= 6600 x 10³
Formula of time period of the satellite
T = 2π R /v₀ , v₀ is orbital velocity
v₀ = √gR , ( if height is small with respect to radius )
T = 2π R /√gR
= 2π√ R /√g
= 2 x 3.14 x √ 6600 x 10³ / √9.8
= 2 x 3.14 x 256.9 x 10 / 3.13
= 5154.41 s
= 5154.41 / 60 minutes
= 85.91 m
85.9 minutes.
2 ) No of sunrise per day = no of rotation per day
= 24 x 60 / 85.9
= 16.76
or 17 sunrises.
