Answer:

a) t = 56.34 minutes

b) v = 5.32mph

c) t = 47.22 minutes

d) v = 6.35 mph

Explanation:

Given;

The speed of Ilya and Anya are

Run = 8.90mph

Walk = 3.80mph

distance = 5.00 miles

a) anya walk half the distance and run half the distance.

Speed = distance/time

time = distance/speed

t1 = 5×0.5/3.80 = 0.658hr

t2 = 5×0.5/8.90 = 0.281hr

t = t1 + t2 = 0.658+0.281 = 0.939hr × 60minutes/hr

t = 56.34 minutes

b) average speed = total distance/total time taken

v = 5.00miles/0.939hr = 5.32mph

c) Ilya walk half the time and run half the time.

t1 = t2 = t/2

Distance = speed × time

Substituting the values.

5 = 3.80(t/2) + 8.90(t/2)

5 = 12.70(t/2)

t = 10/12.70

t = 0.787 hr × 60 minutes/hr

t = 47.22 minutes

d) average speed = 5miles/0.787hr

v = 6.35 mph

**Answer:**

Mechanical resonance is the tendency of a mechanical system to respond at greater amplitude when the frequency of its oscillations matches the system's natural frequency of vibration (its resonance frequency.

**Explanation:**

**Explanation:**

The given data is as follows.

Dielectric constant, K = 3.0

Area of the plates (A) = 0.021

Distance between plates (d) =

Maximum electric field (E) =

Now, we will calculate the capacitance as follows.

C =

=

=

= F

Formula to calculate electric charge is as follows.

E =

or, Q = (as )

=

=

Formula to calculate the energy is as follows.

U =

=

=

=

or, =

Thus, we can conclude that **the maximum energy that can be stored in the capacitor is .**

In the given question, we already know

Work done = 150 joules

Force = 120 Newton

Now we know from the study of physics that

Distance (D) = Work done / Force

(a) To find the height upto which the backpack has been lifted,

D = Work done / Force

= 150 / 120

= 15 / 12

= 5 / 4

= 1.25

So the backpack was lifted to a height of 1.25 metres.

(b) Now we have the find the weight of the backpack in pounds

We know that 1 pound = 4.448 Newton

So if

4.448 Newton = 1 pound

Then

120 Newton = (120 / 4.448) pounds

= 26.978 pounds

So the backpack weighed 26.98 pounds.