What language is this?? So I can translate it and answer your question
Explanation:
Given: time= 3 minutes
Distance =18 km
Speed = distance / time
= 18/3
=6 km/min
(I don't know in what unit u want the answer)
Hope this helps and answers your question..
Good Luck
We know, Frequency = speed / wavelength
f = 341 / 0.8
f = 426.25 Hz
In short, Your Answer would be 426.25 Hz
Hope this helps!
Answer:
θ = 12.60°
Explanation:
In order to calculate the angle below the horizontal for the velocity of the hockey puck, you need to calculate both x and y component of the velocity of the puck, and also you need to use the following formula:
(1)
θ: angle below he horizontal
vy: y component of the velocity just after the puck hits the ground
vx: x component of the velocity
The x component of the velocity is constant in the complete trajectory and is calculated by using the following formula:

vo: initial velocity = 28.0 m/s
The y component is calculated with the following equation:
(2)
voy: vertical component of the initial velocity = 0m/s
g: gravitational acceleration = 9.8 m/s^2
y: height
You solve the equation (2) for vy and replace the values of the parameters:

Finally, you use the equation (1) to find the angle:

The angle below the horizontal is 12.60°
Answer:
b friction
Explanation:
Contact forces
Contact forces are forces that act between two objects that are physically touching each other. Examples of contact forces include:
Reaction force
An object at rest on a surface experiences reaction force. For example, a book on a table.
A box rests on a table. There are two arrows, equal in size but going in opposite directions, up and down, from the point where the box meets the table.
Tension
An object that is being stretched experiences a tension force. For example, a cable holding a ceiling lamp.
A box hangs from a rope. Two arrows which are equal in size act upwards and dowards from the top and bottom of the rope.
Friction
Two objects sliding past each other experience friction forces. For example, a box sliding down a slope.
A box rests on an incline. There are three arrows; one acting vertically downwards from the centre of the box’s base. One arrow acts perpendicular to the incline. One arrow acts up the incline.
Air resistance
An object moving through the air experiences air resistance. For example, a skydiver falling through the air.
A box falls from the sky. Two arrows, equal in size and opposite in direction act upwards from the box and downwards from the box
When a contact force acts between two objects, both objects experience the same size force, but in opposite directions. This is Newton's Third Law of Motion.