The right answer to this question is A. a crest that is toppling over. When a surfer rides an ocean wave on her surfboard, she is actually riding on a crest. The crest is the point on a wave with the maximum value or upward displacement within a cycle.
The work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
<h3>What is normal force?</h3>
The force of contact is called the normal force. When the two surfaces are in contact with each other, then the normal force acts.
This force is applied by the solid bodies on each other in order to prevent the passing through each other.
A box slides down a frictionless incline, gaining speed. For this box, the value of work done by normal force has to be found out. Let's analyze the given condition.
- The body is gaining the speed, which means there is a change in kinetic energy.
- The change in kinetic energy is equal to the work done.
- The friction force is the product of coefficient of the friction and normal force.
- The friction force for the given case is zero. Thus, the normal force must be equal to the zero.
Thus, the work done by the normal force n when the box slides down a frictionless incline and gaining speed is zero.
Learn more about the normal force here;
brainly.com/question/10941832
Answer:
Explanation:
To find Sammy's course you have to add the two velocities (vectors), 18 mph 327º and 4 mph 60º.
To add the two vectors analytically you decompose each vector into their vertical and horizontal components.
<u>1. 18 mph 327º</u>
- Horizontal component: 18 mph × cos (327º) = 15.10 mph
- Vertical component: 18 mph × sin (327º) = - 9.80 mph

<u>2. 4 mph 60º</u>
- Horizontal component: 4 mph × cos (60º) = 2.00 mph
- Vertical component: 4 mph × sin (60º) = 3.46 mph

<u>3. Addition:</u>
You add the corresponding components:

To find the magnitude use Pythagorean theorem:
<u>4. Direction:</u>
Use the tangent ratio:
Find the inverse: