Speed has the dimensions of distance divided by time. The SI unit of speed is themetre<span> per second, but the most common unit of speed in everyday usage is the kilometre per </span>hour<span> or, in the US and the UK, miles per </span>hour<span>. For air and marine travel the knot is commonly used.</span>
Answer:
Explanation:
The horizontal component of force applied = 7.97 cos 26.2 = 7.15 N.
Vertical component in upward direction = 7.97 sin 26.2 = 3.52 N.
Since the body is moving with uniform velocity, friction force will equalize the external horizontal component = 7.15 N.
So frictional force = 7.15 N.
a) Work done by rope force per second = force in horizontal direction x displacement per second = 7.15 x 4.33 = 30.95 J
b) Increase in thermal energy per second will be due to negative work done by frictional force = work done by external force = 30.95 J.
c) Normal force acting downwards = weight - vertical component of external force = 4.36 x 9.8 - 3.52 = 39.21 N
coefficient of friction = friction force / normal force = 7.15 / 39.21 = 0.18
Answer:
C)a lack of supporting empirical evidence
Explanation:
A scientific reasoning can be rendered invalid if empirical evidences are lacking. Empirical evidences are usually a product of observations or experiments.
When these are lacking or cannot be gathered, scientific observations or sometimes reasoning can be rendered as invalid because there is no ground to prove them.
Answer:
No
Explanation:
Recall that the hierarchy of wavelength color from minimum wavelength to maximum wavelength is:
and
As a result, blue light has a higher energy level than green and red light.
As a result, the surface glows due to the blue LED. The green LED, on the other hand, would not allow the surface to glow as much as the red LED, which has a lower energy level when compared to the green light. As a result, the red LED would not allow the surface to glow as well.
