# Physics

## a turbine is to operate at 300 rpm under a net head of 400 m. if cv=0.98 what is the velocity?

a turbine is to operate at 300 rpm under a net head of 400 m. if cv=0.98 what is the velocity? EXPERT ANSWER Given, Net head, H net = 400m Co-efficient of velocity, Cv = 0.98 The turbine speed, N = 300rpm Therefore, the turbine is Francis turbine Now, Velocity, V = Cv × √(2gHnet) …

## B.4) A harmonic wave with a frequency of 80Hz and an amplitude of 0.025m travels along a string to the right with a speed of 12m/s. a) Write a suitable wave function for this wave. b) Find the maximum speed of a point on the string. c) Find the maximum acceleration of a point on the string.

EXPERT ANSWER Given f=80Hz Amplitude A= 0.025m Speed v=12m/s We know v^2= w^2(A^2-x^2) Where w=angular frequency=2πf=2(3.1415) (80) w= 502.6rad/s A^2-x^2=(v/w) ^2=(12/502.6) ^2 =0.00057 x^2=(0.025) ^2-0.00057 =5.49*10^-5 x=0.0074m wave function x = A cos wt=0.025 cos 502.6t Maximum speed vo=Aw vo=(0.025) (502.6) =12.56 m/s Maximum acceleration ao=Aw^2 ao=(0.025) (502.6^2) = 6315m/s^2

## A. An engineer builds two simple pendula. Both are suspended from small wires secured to the ceiling of a room. Each pendulum hovers 2 cm above the floor. Pendulum 1has a bob with a mass of 10 kg. Pendulum 2 has a bob with a mass of 100 kg. Describe how the motion of the pendula will differ if the bobs are both displaced by 12o.

A. An engineer builds two simple pendula. Both are suspended from small wires secured to the ceiling of a room. Each pendulum hovers 2 cm above the floor. Pendulum 1has a bob with a mass of 10 kg. Pendulum 2 has a bob with a mass of 100 kg. Describe how the motion of the …

## 1. Does the period of a simple pendulum depend on the mass? 2. Is the period constant over small angles? Does it vary when one reaches larger angles? 3. Does the period depend on the length of the pendulum? 4. If a single period takes exactly 1.00 second, how long does a period take on the moon? If the gravitational acceleration of the moon is 1/6 of that on the earth

1. Does the period of a simple pendulum depend on the mass?2. Is the period constant over small angles? Does it vary when one reaches larger angles?3. Does the period depend on the length of the pendulum?4. If a single period takes exactly 1.00 second, how long does a period take on the moon? If …