Answer:
option (b)
Explanation:
Let the resistance of each resistor is R.
In series combination,
The effective resistance is Rs.
rs = r + R + R + .... + n times = NR
Let V be the source of potential difference.
Power in series
Ps = v^2 / Rs = V^2 / NR ..... (1)
In parallel combination
the effective resistance is Rp
1 / Rp = 1 / R + 1 / R + .... + N times
1 / Rp = N / R
Rp = R / N
Power is parallel
Rp = v^2 / Rp = N V^2 / R ..... (2)
Divide equation (1) by equation (2) we get
Ps / Pp = 1 / N^2
Answer:
5.5 m/ sec
Explanation:
Because the inclined surface is frictionless so we can assume that total change of energy is zero
i-e ΔE = 0
Or we can say that difference between final and initial energy is zero i-e
Ef- Ei =0
Where,
Ef= final energy at the top of the ramp= KEf+PEf
Ei= Initial energy at the bottom of the ramp=KEi+PEi
So we have
(KEf+PEf)-(KEi+PEi)=0
==>KEf-KEi+PEf-PEi=0 -------------(1)
KEf = mgh = 200×9.8×h
Where h= Sin 22 = h/d= h/4.1
or
0.375×4.1=h
or h= 1.54 m
So, PEf= 200×9.8×1.54=3018.4 j
and KEf= 1/2 m
= 0.5×200×0=0 j
PEi= mgh = 200×9.8×0=0 j
KEi= 1/2 m
=0.5×200×
=100
j
Put these values in eq 1, we get;
0-100
+3018.4-0=0
-100
=-3018.4
==>
= 30.184
==> Vi = 
Answer:
a. 1/1000 sec
Explanation:
Shutter speed is the length of time that the film you’re photographing is being exposed to the scene in film photography. However, in digital photography, shutter speed is the length of time that the image sensor sees the scene the photographer is trying to capture.
For shutter speeds, the greater the denominator the higher the speed and the lower the denominator, the lower the speed.
Thus, the fastest one is option A.
Answer:
d = 142.5 m
Explanation:
This is a vector exercise. Let's calculate how much the boat travels in the 40s
d₀ =
t
d₀ = 0.75 40
d₀ = 30 m
Let's write the kinematic equations
Boat
x = d₀ +
t
x = 0 +
t
At the meeting point the coordinate is the same for both
d₀ +
t =
t
t (
-
) = d₀
t = d₀ / (
-
)
The two go in the same direction therefore the speeds have the same sign
t = 30 / (0.95-0.775)
t = 150 s
The distance traveled by man is
d =
t
d = 0.95 150
d = 142.5 m
Answer:
describe three different ways to change your velocity when youre riding a bike?