<span>The correct option is C. Gravity, and the complete sentence is: "The force of gravity is the force at which the Earth attracts another object towards itself". In fact, the force of gravity between two objects is given by
</span>
<span>
where G is the gravitational constant, m1 and m2 the masses of the two objects, r their separation. If we take the Earth as one of the two objects, then m1 represents the Earth's mass, m2 the mass of the object and r the distance between the center of Earth and the object, and F is the gravitational force at which the Earth attracts the object.</span>
Answer:
d= 794.4 cmExplanation:
Given that
Speed ,V= 286 km/h
V=79.44 m/s
Given that time ,t= 100 ms
t= 0.1 s
We know that ( if acceleration is zero)
Distance = Speed x time
d= V t
Now by putting the values in the above equation
d = 79.44 x 0.1 m
d= 7.944 m
We know that 1 m = 100 cm
d= 794.4 cm
Answer: 2.94×10^8 J
Explanation:
Using the relation
T^2 = (4π^2/GMe) r^3
Where v= velocity
r = radius
T = period
Me = mass of earth= 6×10^24
G = gravitational constant= 6.67×10^-11
4π^2/GMe = 4π^2 / [(6.67x10^-11 x6.0x10^24)]
= 0.9865 x 10^-13
Therefore,
T^2 = (0.9865 × 10^-13) × r^3
r^3 = 1/(0.9865 × 10^-13) ×T^2
r^3 = (1.014 x 10^13) × T^2
To find r1 and r2
T1 = 120min = 120*60 = 7200s
T2 = 180min = 180*60= 10800s
Therefore,
r1 = [(1.014 x 10^13)7200^2]^(1/3) = 8.07 x 10^6 m
r2 = [(1.014 x 10^13)10800^2]^(1/3) = 10.57 x 10^6 m
Required Mechanical energy
= - GMem/2 [1/r2 - 1/r1]
= (6.67 x 10^-11 x 6.0 x 10^24 * 50)/2 * [(1/8.07 × 10^-6 )- (1/10.57 × 10^-6)]
= (2001 x 10^7)/2 * (0.1239 - 0.0945)
= (1000.5 × 10^7) × 0.0294
= 29.4147 × 10^7 J
= 2.94 x 10^8 J.
Answer:
By turning the vehicle "ON" position you can check to see if the gauges light works.
When we switch ON or turn a key to ON the engine, we can find all the gauges working or not.
That's a great idea ! A wind turbine (windmill) or solar panels
on the roof of every WalMart, but don't stop there. Let K-Mart,
Target, Sears, Macy's, 7-11, McDonald's, and Subway in on it too.
In fact, why not place them on the roof of every house and
apartment building too ?
Just one question: Who's going to pay for them ?
_________________________________________________
The biggest single year-round residential use of energy in the
USA is to heat up and keep a ready supply of hot water. So the
single biggest residential use of energy could be eliminated with
a simple solar water heater on the roof of every house. From my
own personal observation, I know that Israel is there now, but here
in the USA, it's apparently not worth the time, effort, or expense ! ? !
