Answer:
C
Step-by-step explanation:
Number 4
Answer:
a = M -Gh/G
Step-by-step explanation:
in order to make a the subject of fomular , you will open the bracket first and then combine the like terms.
G(a + h) = M
Ga + Gh = M
Ga = M - Gh
since G is disturbing a from standing alone, we divide both sides by G
Ga/G = M- Gh/ G
a = M -Gh/G
Height of each floor = 5 meters
time to travel from the first floor to 68th floor = ?
Speed of elevator = 7.5m/s
While an elevator travels from 1st floor to 68th floor, we will multiply the height of floor with 67 to get the distance covered by the elevator form 1st floor to 68th floor, the height of 68th floor will not be counted in the distance because an elevator reaches the 68th floor not covered the height of that floor.
Distance = 5 x 67 = 335m
Now calculate the time by using the formula;
time = distance / speed
= 335m / 7.5m/s
= 44.667 seconds
Thus, an elevator will take 44.667 seconds to reach 68th floor.
