Answer:
Explanation:
assume
M= mass of Mars
m=mass of phobos
r=orbital radius
T=period
we can apply F=ma to this orbital motion (considering the cricular motion laws)
where,
and a=rω^2
where ω=
and G is the universal gravitational constant.
G = 6.67 x 10-11 N m2 / kg2
Answer:
v = 87.57 m/s
Explanation:
Given,
The initial velocity of the car, u = 0
The final velocity of the car, v = 60 mi/hr
The time period of car, t = 8 s
= 0.00222 hr
The acceleration of the car is given by the formula,
a = (v -u) / t
= 60 / 0.00222
= 27027 mi/hr²
If the car has initial velocity, u = 50 mi/hr
The time period of the car, t = 5.0 s
= 0.00139 hr
Using first equations of motion
<em> v = u + at</em>
= 50 + (0.00139 x 27027)
= 87.57 mi/hr
Hence, the final velocity of the car, v = 87.57 mi/hr
Answer:
Explanation:
1) True. The stored energy (U) is proportional to the electric field strength (E). The electric field strength decreases when a dielectric is introduced hence inserting a dielectric decreases U.
2) False. From the formula 
, capacitance is inversely proportional to distance hence if the distance is doubled, capacitance decreases.
3) False. As the distance between the electric field and the object increases, its electric field decreases.
4) False. If a dielectric is inserted, the plates are further separated. Q stays the same.
5) True. The electric field strength decreases when a dielectric is introduced and capacitance is inversely proportional to electric field hence Inserting a dielectric increases C
6) True. If a dielectric is inserted, the plates are further separated. Q stays the same.
7) True. When the distance is doubled, U increases
Resistance = (voltage) / (current)
Resistance = (100 V) / (20 A)
<em>Resistance = 5 Ω (D)</em>
Answer:
12 cm and 0.4
Explanation:
f = - 20 cm, u = - 30 cm
Let v be the position of image and m be the magnification.
Use lens equation
1 / f = 1 / v - 1 / u
- 1 / 20 = 1 / v + 1 / 30
1 / v = - 5 / 60
v = - 12 cm
m = v / u = - 12 / (-30) = 0.4
