Let us consider body moves a distance S due to the force F.
Hence the work by the body W = FS
If the force is not along the direction of displacement,then the work by a body for travelling a distance S will be -
![W=[ Fcos\theta]*S](https://tex.z-dn.net/?f=W%3D%5B%20Fcos%5Ctheta%5D%2AS)
where 
is the component of the force along the direction of displacement.
As per the question the power P is given as -
Hence alternative definition of power P = F.V
Answer:
Waves with high frequencies have shorter wavelengths that work better than low frequency waves for successful echolocation.
Explanation:
To understand why high-frequency waves work better than low frequency waves for successful echolocation, first we have to understand the relation between frequency and wavelength.
The relation between frequency and wavelength is given by
λ = c/f
Where λ is wavelength, c is the speed of light and f is the frequency.
Since the speed of light is constant, the wavelength and frequency are inversely related.
So that means high frequency waves have shorter wavelengths, which is the very reason for the successful echolocation because waves having shorter wavelength are more likely to reach and hit the target and then reflect back to the dolphin to form an image of the object.
Thus, waves with high frequencies have shorter wavelengths that work better than low frequency waves for successful echolocation.
Answer:
Matter can be changed, but not created or destroyed.
Explanation:
Matter can change for through physical and chemical changes, though this happens, matter is conserved. The same amount of matter exists before and after the change.
Momentum is conserved when carts are collided on a slanting plane.
To find the answer, we need to know about the conversation of momentum.
<h3>What's the conversation of momentum?</h3>
- Conservation of linear momentum says the total momentum before the collision and after the collision remains the same.
- Mathematically, m1u1+m2u2 = m1v1+m2v2
<h3>How is the momentum conserved when collision occurs on a slanting plane?</h3>
- On a slanting plane, the velocity has two components,
- horizontal component
- horizontal component Vertical component
- So, its momentum has also similar two components.
- The momentum is conserved along horizontal direction and vertical direction separately.
Thus, we can conclude that the momentum is conserved when carts are collided on a slanting plane.
Learn more about the conversation of momentum here:
brainly.com/question/7538238
#SPJ4
Answer:
a. 120 W
b. 28.8 N
Explanation:
To a good approximate, the only external force that does work on a cyclist moving on level ground is the force of air resistance. Suppose a cyclist is traveling at 15 km/h on level ground. Assume he is using 480 W of metabolic power.
a. Estimate the amount of power he uses for forward motion.
b. How much force must he exert to overcome the force of air resistance?
(a)
He is 25% efficient, therefore the cyclist will be expending 25% of his power to drive the bicycle forward
Power = efficiency X metabolic power
= 0.25 X 480
= 120 W
(b)
power if force times the velocity
P = Fv
convert 15 km/h to m/s
v = 15 kmph = 4.166 m/s
F = P/v
= 120/4.166
= 28.8 N
definition of terms
power is the rate at which work is done
force is that which changes a body's state of rest or uniform motion in a straight line
velocity is the change in displacement per unit time.
