Answer:
<em>The total time is: t=451.22 sec</em>
<em>The average speed is: V=34.57 m/s</em>
Explanation:
<u>Average speed</u>
The average speed is calculated by dividing the total distance traveled by an object (x) by the total time it took it to travel that distance (t).
Since the student makes the trip in two parts, we have to calculate the total distance and the total time.
We know the distance to school is 7.8 Km = 7,800 m. The student makes his way home over the same distance, thus the total distance is
x=2*7,800 m=15,600 m
The first trip to school was done at an average speed of v1=32.6 m/s. Knowing the distance and speed, we can calculate the time:
The second trip back home was done at an average speed of v2=36.8 m/s. Let's calculate the second time:
The total time is:
The average speed is:
Answer:
The average force exerted on the man by the ground therefore is 153.319.53 N
Explanation:
Given the following information
Mass of man, m = 75 kg
height of fall, h = 0.48 cm
velocity just before landing, v = 4.43 m/s
We therefore have
The work required to break the fall is equal to the kinetic energy of motion, just before touching the ground
Work done = Energy to absorb Kinetic Energy KE = 0.5·m·v²= F·h
Where:
F = Force required to break the fall
Therefore the force, F = (0.5·m·v² )/h
= 0.5×75 kg ×(4.43 m/s)²/(0.0048 m) = 153319.53 N
The average force exerted on him by the ground is therefore
= 153319.53 N.
Answer:
F) The acceleration due to gravity is g/27
Explanation:
According to Newton gravitational law, the gravitational acceleration is directly proportional to the planet mass and inversely proportional to the square of distance.
Since our new planet has a mass of one-third of Earth's and radius 3 times of Earth's. This means the new planet is lighter and further away from the distance. This means g is first reduced by 3 due to smaller mass and then reduced by 9 due to square of 3 times the distance.
The gravitational acceleration on this new planet must be
So F) is the correct answer
We start to see more off the dark side (waning) or more of the light side (waxing) the more of the dark side we see, the less moon there seems to be. The more light side, the more moon.
