Set it up as a direct proportion:
2.0lb/9hb = x/100hb
solve x (100hb •2.0lb)/9hb = 22.2lb
22.2lbs
Answer: 8.81 J
Explanation: The scalar or dot product of 2 vector equals the product of the magnitude of both vectors and the cosine value of the angle between them
Magnitude of vector f (force) as given in the question = 12.5N
Magnitude of length = 0.75m
Angle between vectors = 25°
F. Δr = 12.5 * 0.75 * cos 25
F. Δr = 12.5 * 0.75 * 0.9063
F. Δr = 8.81 J
Using lens equation;
1/o + 1/i = 1/f; where o = Object distance, i = image distance (normally negative), f = focal length (normally negative)
Substituting;
1/o + 1/-30 = 1/-43 => 1/o = -1/43 + 1/30 = 0.01 => o = 1/0.01 = 99.23 cm
Therefore, the object should be place 99.23 cm from the lens.
Answer:
4.13Hz
Explanation:
f1 = 1/t1 = 1/0.022 = 45.45 Hz
f2 = 1/t2 = 1/0.0242= 41.32 Hz
No. of beats
= 45.45- 41.32
~ 4.13Hz