Answer:
The wave speed is calculated below:
Explanation:
Given,
number of waves passed per minute = 8
time period = 1 minute = 60 s
distance between successive wave crests = 20 m
waves passing interval per second =

Now,
wave speed = 20 m ×

=
m/s
= 2.67 m/s
Hence the wave speed is 2.67 m/s.
Answer:
the range or the ball is 48.81 m
Explanation:
given;
Nicole throws a ball at 25 m/s at an angle of 60 degrees abound the horizontal.
find:
What is the range of the ball?
solution:
let Ф = 25°
Vo = 25 m/s
<u>consider x-motion using time of fight: x = Vox * t</u>
where x = R = range
t =<u> 2 Voy </u>
g
R =<u> Vo² sin (2Ф)</u>
g
plugin values into the formula:
R = <u>(25)² sin (2*25) </u>
9.81
R = 48.81 m
therefore, the range or the ball is 48.81 m
Answer:
a) -2.038 m/s²
b) 40.33 mph
c) 312.5 m
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity
s = Displacement
a = Acceleration

Acceleration of the boat is -2.083 m/s² if the boat will stop at 150 m.

Speed of the boat by when it will hit the dock is 18.03 m/s
Converting to mph



Speed of the boat by when it will hit the dock is 40.33 mph

The distance at which the boat will have to start decelerating is 312.5 m
Answer:
The force exerted by the rope on her arms is 273.7 N = 0.274 kN
Explanation:
Step 1: Data given
Mass of the ice skater = 55.6 kg
Velocity = 1.73 m/s
She then moves in a circle of radius 0.608 m around the pole.
Step 2:
Force exterted by the horizontal rope is the centripetal force acting on theice skater:
Fc = M*ac
⇒ with ac = v²/r
Fc = M * v²/r
Fc = 55.6 * 1.73²/0.608
Fc =273.69 N
The force exerted by the rope on her arms is 273.7 N = 0.274 kN