Answer:
630.75 j
Explanation:
from the question we have the following
total mass (m) = 54.5 kg
initial speed (Vi) = 1.4 m/s
final speed (Vf) = 6.6 m/s
frictional force (FF) = 41 N
height of slope (h) = 2.1 m
length of slope (d) = 12.4 m
acceleration due to gravity (g) = 9.8 m/s^2
work done (wd) = ?
- we can calculate the work done by the boy in pushing the chair using the law of law of conservation of energy
wd + mgh = (0.5 mVf^2) - (0.5 mVi^2) + (FF x d)
wd = (0.5 mVf^2) - (0.5 mVi^2) + (FF x d) - (mgh)
where wd = work done
m = mass
h = height
g = acceleration due to gravity
FF = frictional force
d = distance
Vf and Vi = final and initial velocity
wd = (0.5 x 54.5 x 6.9^2) - (0.5 x 54.5 x 1.4^2) + (41 x 12.4) - (54.5 X 9.8 X 2.1)
wd = 630.75 j
A - i think
paying bills online?
Answer:
c) nonzero, directed toward the spaceship
Explanation:
As we know that net gravitational force due to spherical shell inside all its points will always be zero
So if planet is a spherical shell then inside the planet net gravitational force is zero on the people living in it
So when massive spaceship land on the surface of planet then the gravitational force of the spaceship is experienced by the people inside the shell
So here the gravitational force on the people is nonzero and it is towards the spaceship which landed on the surface of planet
The answer is A, Cell. This is the basic structure of a cell.
Let’s come back to the equation of SPEED OF AN ECHO
SPEED =2XDISTANCE/ TIME
So 337*7/2=1179.5 nearest meter =1800 m away
Hope you will get it right