The best thermal conductor is b. metal
Answer:
-5.24 m/s
** The minus sign indicates that the velocity vector points in the opposite direction with respect to the initial direction of the 77.8 kg player **
Explanation:
Hi!
We can solve this problem considering each player as a point particle and taking into account the conservation of linear momentum.
Since the 99.8 kg player is moving towards the 77.8kg, the initial total momentum is:
m1*v1_i + m2*v2_i = (77.8kg)(8.1 m/s) - (99.8kg)(6.9 m/s)
** The minus sign indicates that the velocity vector points in the opposite direction with respect to the initial direction of the 77.8 kg player **
The final total momentum is equal to:
m1*v1_f + m2*v2_f = (77.8 kg)v1_f + (99.8 kg)(3.5 m/s)
The conservation of momentu tell us that:
m1v1_i + m2v2_i = m1v1_f + m2v2_f
Therefore:
v1_f =v1_i + (m2/m1)*(v2_i-v2_f)
v1_f = 8.1 m/s + (99.8 / 77.8) * (-6.9 - 3.5 m/s)
<u>v1_f = -5.24 m/s</u>
We are given
r = 0.6 m
n = 1.5
D = 0.6 m, R1 = 30 cm
R2 = 120 cm
We are asked to get the focal length and the distance of the focal plane from the lens
We use the formula
1 / f = ( n - 1) (1/R1 - 1/R2)
Substituting and solving for f
1/ f = (1.5 - 1) (1/30 - 1/120)
f = 80 cm
The focal length is 80 cm and the distance of the focal plane from the lesn is 80 cm - 30 cm = 50 cm.<span />