Answer:
D
Explanation:
Increasing its height to twice its original value
Which type of energy is converted into mechanical energy when a person walks?
A. Electromagnetic
B. Electrical
C. Nuclear
D. Chemical
That is Chemical, This is because the energy comes from the food we eat and our fat stores and thus it comes from a chemical form.
The spring constant is 
Explanation:
For an object in a simple harmonic motion, the acceleration of the object is related to the displacement by
where
a is the acceleration
is the angular frequency
x is the displacement
The angular frequency is defined as
where
k is the spring constant
m is the mass
Substituting the second equation into the first one, we get
In this problem we have
m = 1 g = 0.001 kg
And at t=0,
x = 43.75 cm
a = -1.754 cm/s
Therefore, we can re-arrange the equation above to find the spring constant:
#LearnwithBrainly
It can cause the water to create algae.
Answer: 7.78m/s
Explanation: As the the skier slide down the height, we assume the motion of a body, slidind down an incline plane.
Force down the plane= [email protected]
Frictional force= umg
u= coefficient of friction
Net force on skier = [email protected] umg
ma = [email protected]
a = g([email protected] - u) = 9.8 (sin 25- 0.2)
a = 9.8 × (0.4226-0.2) = 9.8 × 0.2226
a = 2.18m/s²
Using the formula V² = U² + 2aH
Where H = (10.4+ 3.5)=total height of descent before landing, U= 0.
V = √ 2 × 2.18× 13.9 = √60.604
V = 7.78m/s
