Answer:
a) 147.95 Mpc
Explanation:
Using Hubble's formula
where;
v = radical velocity
= Hubble's constant
d = distance
Given that:
The average radial velocity of galaxies in the Hercules cluster v = 10,800 km/s
Also using = 73 km/s/ Mpc ; we make distance d the subject of the formula:
Then distance d can be written as:
d = 147.95 Mpc
b)
Now, if the Hubble constant had a smaller value, then for a given velocity the distance to the galaxy will increase because distance d is inversely proportional to
i.e
d ∝ 
The mirror formula for curved mirrors is:
where
f is the focal length of the mirror
is the distance of the object from the mirror
is the distance of the image from the mirror
The sign convention that should be used in order to find the correct values is the following:
-
: positive if the mirror is concave, negative if the mirror is convex
-
: positive if the image is real (located on the same side of the object), negative if it is virtual (located on the opposite side of the mirror)
Answer:
Option A
Explanation:
The Equation represents the displacement of the object which is represented by x
so, 
means when time is zero so we replace t with zero in the equation,
now for v which is velocity we need to differentiate the function as the formula for velocity is rate of change of displacement over time so we derivate the equation once and get,
now for 
we insert t = 0 and get
now for a which is acceleration the formula of acceleration is rate of change of velocity over time, so we differentiate the the equation of v(velocity) once or the equation of x(displacement) twice so now we get,
so Option A is your answer.
Remember derivative of a constant is always zero because a constant value has no rate of change has its a constant hence the derivative is 0
