<h2>a) Average velocity in first 4 seconds is 64 ft/s upward</h2><h2>b) Average velocity in second 4 seconds is 63.5 ft/s downward</h2>
Explanation:
a) Given S(t) = 76 + 128t − 16t²
s(0) = 76 + 128 x 0 − 16 x 0² = 76 ft
s(4) = 76 + 128 x 4 − 16 x 4² = 332 ft
Displacement in 4 seconds = 332 - 76 = 256 ft
Time = 4 - 0 = 4 s

Average velocity in first 4 seconds is 64 ft/s upward
a) Given S(t) = 76 + 128t − 16t²
s(4) = 76 + 128 x 4 − 16 x 4² = 332 ft
s(8) = 76 + 128 x 8 − 16 x 8² = 78 ft
Displacement in 4 seconds = 78 - 332 = -254 ft
Time = 4 - 0 = 4 s

Average velocity in second 4 seconds is 63.5 ft/s downward
Answer:
a)Amplitude ,A = 2 mm
b)f=95.49 Hz
c)V= 30 m/s ( + x direction )
d) λ = 0.31 m
e)Umax= 1.2 m/s
Explanation:
Given that
![y=2\ mm\ sin[(20m^{-1})x-(600s^{-1})t]](https://tex.z-dn.net/?f=y%3D2%5C%20mm%5C%20sin%5B%2820m%5E%7B-1%7D%29x-%28600s%5E%7B-1%7D%29t%5D)
As we know that standard form of wave equation given as

A= Amplitude
ω=Frequency (rad /s)
t=Time
Φ = Phase difference
![y=2\ mm\ sin[(20m^{-1})x-(600s^{-1})t]](https://tex.z-dn.net/?f=y%3D2%5C%20mm%5C%20sin%5B%2820m%5E%7B-1%7D%29x-%28600s%5E%7B-1%7D%29t%5D)
So from above equation we can say that
Amplitude ,A = 2 mm
Frequency ,ω= 600 rad/s (2πf=ω)
ω= 2πf
f= ω /2π
f= 300/π = 95.49 Hz
K= 20 rad/m
So velocity,V
V= ω /K
V= 600 /20 = 30 m/s ( + x direction )
V = f λ
30 = 95.49 x λ
λ = 0.31 m
We know that speed is the rate of displacement

![U=2\ mm\ sin[(20m^{-1})x-(600s^{-1})t]](https://tex.z-dn.net/?f=U%3D2%5C%20mm%5C%20sin%5B%2820m%5E%7B-1%7D%29x-%28600s%5E%7B-1%7D%29t%5D)
![U=1200\ cos[(20m^{-1})x-(600s^{-1})t]\ mm/s](https://tex.z-dn.net/?f=U%3D1200%5C%20cos%5B%2820m%5E%7B-1%7D%29x-%28600s%5E%7B-1%7D%29t%5D%5C%20mm%2Fs)
The maximum velocity
Umax = 1200 mm/s
Umax= 1.2 m/s
Answer:
Potential energy =mass* acceleration due to gravity * height
mass*acceleration due to gravity =weight
hence potential energy of the puppy= weight * height
=18*2
=36 joule
Answer:
Kinetic energy is the energy an object has because of its motion. If we want to accelerate an object, then we must apply a force. Applying a force requires us to do work. After work has been done, energy has been transferred to the object, and the object will be moving with a new constant speed.