Answer: As a person pushes a box across a floor, the energy from the person's moving arm is transferred to the box and floor become warm during this process, energy is conserved
Answer:
density = 5520 kg/m^3
Explanation:
given that
radius of earth = 6378 km
G = 6.67 x 10⁻¹¹ m³/kg.s²
g = 9.80 m/s²
we know,
mass of earth
M = 5.972 x 10²⁴ kg
density =
V = volume of the earth = 4/3πr³
V = 4/3 x 3.14 x (6378 x 10³)³
V = 1.08 x 10²¹ m³
density = 
density = 5.52 x 10³ kg/m^3
density = 5520 kg/m^3
6b: impulse is change in momentum. Change in momentum p=m[v(final)-v(initial). Final velocity is zero and initial velocity is the one you calculated before impact: -15.7 since it’s going down. Now plug in numbers and you get 78.5 in the upward direction.
6c: change in momentum p=Ft. we already calculated change in momentum. So plug it into equation and solve for t. 78.5/655= 0.119 s
Apply the same idea for question 7. Hope this helped
Answer:
0.47m3
Explanation:
Volume = Mass / Density
In this case:
Mass - 1280 kg
Density - 2700kg/m3
1280 / 2700 = 0.4740741m3
When this is rounded off ( 2 d.p ):
0.47 m3
HOPE THIS HELPED
