Answer:
a) No difference
Explanation:
Since the billiard balls are identical , they have the same mass. Also they have the same speed
Since the angular momentum is conserved and the total energy is conserved ( if we assume elastic collision)
1/2 m1 * v i1² +1/2 m2 * v i1² = 1/2 m1 * v f1² +1/2 m2 * v f2²
where m= mass , vi= initial velocity , vf= final velocity
since m1=m2=m , vi1=vi2=vi
1/2 m1 * v i1² +1/2 m2 * v i1² = 1/2 m1 * v f1² +1/2 m2 * v f2²
m * v i² = 1/2 m (v f1² +v f2² )
vi² = 1/2(v f1² +v f2² )
since the 2 balls are indistinguishable from each other (they have identical initial mass and velocity) there is no reason for a preferential speed for one of the balls and therefore its velocities must be equal . Thus vf1=vf2=vf
therefore
v i² = 1/2(v f1² +v f2² ) = v i1² = 1/2* 2vf² = vf²
and thus
vi= vf
in conclusion, there is no difference in speed after the rebound
Answer:
378 KWh
Explanation:
We'll begin by converting 1.2×10³ W to KW. This can be obtained as follow:
10³ W = 1 KW
Therefore,
1.2×10³ W = 1.2×10³ W × 1 KW / 10³ W
1.2×10³ W = 1.2 KW
Next, we shall convert 6.3×10² mins to hours (h). This can be obtained as follow:
60 mins = 1 h
Therefore,
6.3×10² mins = 6.3×10² mins × 1 h / 60 mins
6.3×10² mins = 10.5 h
Finally, we shall determine the electrical energy in KWh used for 1 month (i.e 30 days). This can be obtained as follow:
Power (P) = 1.2 KW
Time (t) for 1 month (30 days) = 10.5 h × 30
= 315 h
Energy (E) =?
E = Pt
E = 1.2 × 315
E = 378 KWh
Thus, the electrical energy used for 1 month (i.e 30 days) is 378 KWh.
The volume of water will increase . If yu subtract the original volume from the new volume of water you will get the volume of the small ball.
Answer:
20
Explanation:
AB, AC, AD, AE, BC, BD, BE, ....
