Answer:
The ladder is moving at the rate of 0.65 ft/s
Explanation:
A 16-foot ladder is leaning against a building. If the bottom of the ladder is sliding along the pavement directly away from the building at 2 feet/second. We need to find the rate at which the top of the ladder moving down when the foot of the ladder is 5 feet from the wall.
The attached figure shows whole description such that,
.........(1)

We need to find,
at x = 5 ft
Differentiating equation (1) wrt t as :



Since, 

At x = 5 ft,


So, the ladder is moving down at the rate of 0.65 ft/s. Hence, this is the required solution.
R2^ 2 / R1 ^2 = g1 / g2 = 38
<span>R2 = R1 x √38 = 6.1644* R1 </span>
<span>R2 = 6.1644 x 6378 000 = 39316632.5 m</span>
The most important measure is awhips
Answer:
Option D is the correct answer.
Explanation:
Since value of angular acceleration is constant, the body has only centripetal acceleration.
Centripetal acceleration

We have radius = 7.112 cm = 0.07112 m
Frequency, f = 1975 rpm = 32.92 rps
Angular frequency, ω = 2πf = 2 x π x 32.92 = 206.82 rad/s
Substituting in centripetal acceleration equation,

Option D is the correct answer.
(amount of heat)Q = ? , (Mass) m= 4 g , ΔT = T f - T i = 180 c° - 20 °c = 160 °c ,
Ce = 0.093 cal/g. °c
Q = m C ΔT
Q = 4 g × 0.093 cal/g.c° × ( 180 °c- 20 °c )
Q= 4×0.093 × 160
Q = 59.52 cal
I hope I helped you^_^