All categories

3 years ago

The average 8-18 year old spends how many hours per day average in front of a screen doing little physical activity

Physics

1 answer:

Ne4ueva [31]3 years ago

5 0

Nearly four hours every day, doing little to no physical activity.

You might be interested in

What is the relationship between inertia and mass?

ivann1987 [24]

Answer:

Explanation:

The greater the mass, the greater the inertia, and vice versa.

Remark: This means that a more massive object has a greater tendency to resist a change in its state of rest or motion.

8 0

3 years ago

A parallel-plate capacitor stores charge Q. The capacitor is then disconnected from its voltage source, and the space between th

Stells [14]

Answer:

The relationship between the initial stored energy $PE_{i}$ and the stored energy after the dielectric is inserted $PE_{f}$ is:

c) $PE_{f} =0.5\ PE_{i}$

Explanation:

A parallel plate capacitor with $C_{o}$ that is connected to a voltage source $V_{o}$ holds a charge of $Q_{o} =C_{o} V_{o}$ . Then we disconnect the voltage source and keep the charge $Q_{o}$ constant . If we insert a dielectric of $\kappa=2$ between the plates while we keep the charge constant, we found that the potential decreases as:

$V=\frac{V_{o}}{\kappa}$

The capacitance is modified as:

$C=\frac{Q}{V} =\kappa\frac{Q_{o}}{V_{o}}=\kappa\ C_{o}$

The stored energy without the dielectric is

$PE_{i}=\frac{1}{2}\frac{Q_{o}^{2}}{C_{o}}=\frac{1}{2}C_{o}V_{o}^{2}$

The stored energy after the dielectric is inserted is:

$PE_{f}=\frac{1}{2}\frac{Q^{2}}{C}=\frac{1}{2}CV^{2}$

If we replace in the above equation the values of V and C we get that

$PE_{f}=\frac{1}{2}\kappa\ C_{o}(\frac{V_{o}}{\kappa})^{2}=\frac{1}{\kappa}(\frac{1}{2}C_{o}V_{o}^{2})$

$PE_{f} =\frac{PE_{i}}{\kappa}$

Finally

$PE_{f} =0.5\ PE_{i}$

5 0

3 years ago

A car accelerates from rest to a speed of 8 m/s over a distance of 16 m. What is the acceleration of the car?

Marina CMI [18]

B because all you do is divide 16 and 8 to find your answer

5 0

3 years ago

Read 2 more answers

9,10,and11 please I want the answer I can't found it

Ede4ka [16]

Q9. Inertia is the tendency of an object to resist any change in its motion.

Q10. A moving object's momentum depends on the object's mass and velocity.

Q11. I believe it would be air resistance. The fluid friction that opposes the motion of object's through the air.

7 0

3 years ago

120mL=____cm3-I really need help!

Ivahew [28]

Answer:

120 mL = 120 cm^3

Explanation:

1 mL is <em>equal</em> to exactly 1 cubic centimeter, so 120 mL = 120 cm^3

4 0

3 years ago