Answer:
m=2
Step-by-step explanation:
<span>Answer:
K = (1/2) mv² + (1/2) Iω², where m is the ball mass, I is the ball's moment of inertia (2/5)mr², and ω is the angular velocity of the ball. Because the ball rolls without slipping, it is easy to see that v=ωr, or r=v/ω. Then,
K = (1/2)mv² + (1/2)(2/5)mr²ω²
= (1/2)mv² + (1/5)mv²
= (7/10)mv²
Setting potential at the top equal to kinetic at the bottom,
mgh=(7/10)mv²
v=âš{(10/7)(gh)}
= [(10/7)(9.8)(0.51)]^(1/2) = 2.672m/s</span>
I think D.
They both rested for 2 minutes, however they did not rest at the same time, but it doesn't say they did that in the option choice.
Hope this helps!
Answer:
The ratio of perimeter of ABCD to perimeter of WXYZ = 
Step-by-step explanation:
First, we have to determine the multiplicative factor of the dimensions for both figures.
Considering sides AB and WX,
multiplicative factor = 
= 1.5
So that:
XY = 6 x 1.5 = 9
YZ = 7 x 1.5 = 10.5
ZW = 7 x 1.5 = 10.5
Perimeter of ABCD = 6 + 7 + 7 + 8
= 28
Perimeter of WXYZ = 9 + 10.5 + 10.5 + 12
= 42
The ratio of the perimeters of the two quadrilaterals can be determined as;
ratio = 
= 
= 
The ratio of the perimeter of ABCD to perimeter of WXYZ is
.
It's definitely A, gotta be.