The car is not moving,or either it is going backwords
Answer:
Mass of the oil drop, 
Explanation:
Potential difference between the plates, V = 400 V
Separation between plates, d = 1.3 cm = 0.013 m
If the charge carried by the oil drop is that of six electrons, we need to find the mass of the oil drop. It can be calculated by equation electric force and the gravitational force as :


, e is the charge on electron
E is the electric field, 


So, the mass of the oil drop is
. Hence, this is the required solution.
1. a=(v-v0)/t
a=14 m/s / 2s
a=7 m/s^2
2. <span>a=(v-v0)/t
</span>a=(30 m/s - 0 m/s) / 12 s
a=2.5 m/s^2
3. <span>a=(v-v0)/t
a=(37 m/s - 22 m/s) / 2 s
a= 7.5 m/s^2
4. </span><span>a=(v-v0)/t
a=(12 km/s - 0 km/s)/8 s
a=1.5 km/s^2
etc</span>
Answer:

Explanation:
As we know that the acceleration due to gravity decreases with height.
At certain height it will get to the half of its value on the surface of the earth.
As we know that the weight on the surface of the earth is given as:

where:
m = mass of the object
g = acceleration due to gravity of the substance
Since mass of the substance is constant so the variation is weight is possible only due to change in the acceleration due to gravity.
<u>We know that the variation of the acceleration due gravity with height is given as:</u>

where:
value to acceleration due to gravity at height h
g = acceleration due to gravity at the earth's surface
h = height of the object
R = radius of the earth = 
according to question the weight becomes half, so,:

is the height a rocket has to go above Earth's surface before its weight is half of what it is on Earth.