Answer:
12.57 km
Step-by-step explanation:
Radius = 4 / 2 = 2 km
Circumference = 2πr = 2π(2) = 4π = 12.57 km
Answer:
Rolling case achieves greater height than sliding case
Step-by-step explanation:
For sliding ball:
- When balls slides up the ramp the kinetic energy is converted to gravitational potential energy.
- We have frictionless ramp, hence no loss due to friction.So the entire kinetic energy is converted into potential energy.
- The ball slides it only has translational kinetic energy as follows:
ΔK.E = ΔP.E
0.5*m*v^2 = m*g*h
h = 0.5v^2 / g
For rolling ball:
- Its the same as the previous case but only difference is that there are two forms of kinetic energy translational and rotational. Thus the energy balance is:
ΔK.E = ΔP.E
0.5*m*v^2 + 0.5*I*w^2 = m*g*h
- Where I: moment of inertia of spherical ball = 2/5 *m*r^2
w: Angular speed = v / r
0.5*m*v^2 + 0.2*m*v^2 = m*g*h
0.7v^2 = g*h
h = 0.7v^2 / g
- From both results we see that 0.7v^2/g for rolling case is greater than 0.5v^2/g sliding case.
Answer:
area of rectangle=l×b=2.4×5.8=13.92cm²
Answer:
C. (1/2)acsinA
Step-by-step explanation:
Given is that, A, B, and C are the measures of the angles of a triangle and a, b, and c are the lengths of the sides opposite the corresponding angles.
So, the expression that does not represent the area of the triangle is :
C. (1/2)acsinA
