Given this measurement 2642 ft, how many significant figures are there?

Consider a parachutist that has reached terminal velocity. which of the following is true? A.) The acceleration of the parachuti

trasher [3.6K]

The correct answer is:
<span>B.) At terminal velocity there is no net force

In fact, when the parachutist reaches the terminal velocity, his velocity does not change any more. It means that the acceleration acting on the parachutist is zero, and for Newton's second law, this means the net force acting on him is zero:
</span> $\sum F = ma = 0$
<span>because the acceleration is zero: a=0.
This also means that the two relevant forces acting on the parachutist (gravity, downward, and air resistance, upward) are balanced to produce a net force equal to zero.</span>

8 0

3 years ago

If two objects of the same size move through the air at different speeds, which encounters the greater air resistance?a. The fas

blagie [28]

Answer:

Option A is correct.

(The faster object encounters more resistance)

Explanation:

Option A is correct. (The faster object encounters more resistance)

Air resistance depends on various factors:

Speed of the object
Cross-sectional area of the object
Shape of the object

Formula:

$F=\frac{1}{2}C_d\rho A v^{2}$

As the speed of the object increases the amount of Air resistance/drag increases on the object, as the above formula shows direct relation between Air resistance/drag and velocity i.e F ∝ v^2.

6 0

3 years ago

A 0.5-kilogram apple falls from a height of 2 meters to 1.50 meters. Ignoring frictional effects, what is the kinetic energy of

spin [16.1K]

The final kinetic energy of the ball is 2.45 J

Explanation:

We can solve this problem by using the law of conservation of energy.

In absence of frictional effect, the mechanical energy of the apple must be conserved during the fall. So we can write:

$U_i +K_i = U_f + K_f$

where :

$U_i$ is the initial potential energy, at the top

$K_i$ is the initial kinetic energy, at the top

$U_f$ is the final potential energy, at the bottom

$K_f$ is the final kinetic energy, at the bottom

By explicing the potential energy, we can rewrite the equation as:

$mgh_i + K_i = mgh_f + K_f$

where:

m = 0.5 kg is the mass of the apple

$g=9.8 m/s^2$ is the acceleration of gravity

$h_i = 2 m$ is the initial height

$h_f=1.50 m$ is the final height

The initial kinetic energy is zero, since the ball starts from rest:

$K_i = 0$

Therefore we can solve the equation for $K_f$ , the final kinetic energy of the ball:

$K_f = mg(h_i-h_f)=(0.5)(9.8)(2-1.50)=2.45 J$

Learn more about kinetic energy and potential energy:

brainly.com/question/6536722

brainly.com/question/1198647

brainly.com/question/10770261

#LearnwithBrainly

3 0

3 years ago

Read 2 more answers

Harmfful effect of earthquake

Snowcat [4.5K]

Answer:

Death, Destruction, Loss of home

5 0

3 years ago

Read 2 more answers

Compare the forces in a small nucleus to the forces in a large nucleus

pochemuha

The comparison of the forces in a small nucleus to the forces of a large one is the fact that they are capable of holding the protons and neutrons which made it no matter what their size may be. Therefore, as long as there is a nucleus, their forces can both hold together the two atoms tight.

6 0

3 years ago