Explanation:
Image distance, v = -17 cm (-ve for virtual image)
Radius of curvature of concave mirror, R = 39 cm
Focal length, f = -19.5 cm (-ve for a concave mirror)
(a) Using mirror's formula as :


u = 132.6 cm
So, the object is placed 132.6 cm in front of the mirror.
(b) Magnification of the mirror, 

m = -0.128
Hence, this is the required solution.
M1*V1 + M2*V2 = M1*V + M2*V.
1400*25 + 1800*20[180+40]=1400*V+1800*V.
Divide both sides by 100:
14*25 + 18*20[220o] = 14V + 18V.
350 + 360[220o] = 32V.
350 - 276-231i = 32V.
74 - 231i = 32V.
242.6[-72.2o] = 32V.
V = 7.6m/s[-72.2o]=7.6m/s[72o] S. of E.
Answer:
w = 706.32 [N]
Explanation:
The force due to gravitational acceleration can be calculated by means of the product of mass by gravitational acceleration.
w = m*g
where:
w = weight [N] (units of Newtons)
m = mass = 72 [kg]
g = gravity acceleration = 9.81 [m/s²]
Then we have:
![w = 72*9.81\\w = 706.32 [N]](https://tex.z-dn.net/?f=w%20%3D%2072%2A9.81%5C%5Cw%20%3D%20706.32%20%5BN%5D)