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.
Answer:
4.25 s
Explanation:
Given:
angular acceleration'α'= 1.8 rad/s²
angle 'θ'= 45 rad
time 't'= 4s
initial angular velocity '
'=0
as we know that,
θ= 
t + 
45 = 4 + (0.5 x 1.8 x 16)
45- 14.4 = 4
30.6 = 4
= 7.65
Next is to find t by using the equation
= + 
7.65= 0 + (1.8)
= 7.65/1.8
= 4.25 s
Therefore, At the start of 4s interval the motion is at 4.25 second
I’m unsure of the answer, but it is not b.
Answer:
To unlock a door and indicate to the person that the door is now unlocked
Explanation:
Schools all have doors locked. Visitors/parents need to press a button. That creates a buzz sound in the office, secretary presses a button to unlock the door. The person trying to enter the school hears a buzz and the secretary telling them to enter the building.
Mass and energy are equivalent. I'm doing the same test right now.
