Hello please help i’ll give brainliest

When you skid to a stop on your bike, you can significantly heat the small patch of tire that rubs against the road surface. Sup

Lunna [17]

Answer:

$E=14.4\ J$

Explanation:

In this case the kinetic energy of the bike is converted into the heat energy between the area of contact of tyre and the road. This happens due to the work done by the frictional force between the surface to stop the relative motion between the road and the tyre.

Given:

normal force on the rear tyre, $N=45\ N$

(as given in the question that the rear tyre supports half the combined weight of the bike and the rider.)

distance dragged while stopping the tyre, $s=0.4\ m$

coefficient of kinetic friction between the surfaces, $\mu=0.8$

<u>Now, frictional force between the surfaces:</u>

$f=\mu.N$

$f=0.8\times 45$

$f=36\ N$

<u>Now, the work done by the kinetic friction:</u>

$W=f.s$

$W=36\times 0.4$

$W=14.4\ J$

According to the energy conservation this amount of energy is converted into thermal energy between the surfaces in contact, i.e. road and the tyre.

5 0

3 years ago

Two resistors connected in series have an equivalent resistance of 724.5 Ω, when they are connected in parallel, their equivalen

dybincka [34]

Answer:

544.65 ohm and 179.84 ohm

Explanation:

Hello

Let

Resistor 1 (R1) and Resistor 2 (R2)

in series $R_{eq} =R1+R2$

in parallel

$\frac{1}{R_{eqp} } =\frac{1}{R1} +\frac{1}{R2}\\\\R1=R_{eqs} -R2\\\\R1 =724.5-R2 (equation 1)\\ R_{eqp}}=\frac{R1*R2}{R1+R2}\\\\\ 135.2 = \frac{R1*R2}{R1+R2}(equation 2)\\\\\\\\replacing 1 in \ 2\\\\probema data$

$135.2=\frac{(724.5-R2)(R2)}{724.5-R2+R2} }\\135.2=\frac{(-R_{2} ^{2}+724.5R2) }{724.5}\\ 135.2*724.5=-R_{2} ^{2}+724.5R_{2}\\\\R_{2} ^{2} -724.5R_{2} +97952.4 =0\\R_{2} =\frac{724.5 \±\sqrt{(-724.5^{2})-4(1)(97952.4) } }{2(1)}\\R_{2} =\frac{724.5\±\sqrt{(133092.25) } }{2(1)}\\\\R_{2} =\frac{724.5+364.81810}{2} \\R_{2} =544.65 ohm\\\\R_{2} =\frac{724.5-364.81810}{2} =179.84 ohm$ \\\\

let R2=544.65 and replace in equation 1

R1=724.5-544.65

R1=179.85

so, the resistors are 544.65 ohm and 179.84 ohm

Have a great day

7 0

4 years ago

A particle moves in a straight line so that time t seconds its displacement is x metres from a fixed point is given by x=3t^2 +2

Andru [333]

Answer:

-5 meters

Explanation:

x = 3t² + 2t − 5

The initial displacement is when t = 0.

x = 3(0)² + 2(0) − 5

x = -5

6 0

4 years ago

A 15.0 cm diameter circular loop of wire is placed with the plane of the loop parallel to the uniform magnetic field between the

velikii [3]

Answer:0.0144 tesla

Explanation:

Magnetic field strength is the same as Magnetomotive force

B= I/2πr

B=magnetic field strength

I=current

r=radius=0.15/2=0.75m

Area=πr2= 1.77m2

torqueT= NIABsin theta

B= T/NIABsin theta

B=0.135/1 * 5.3 * 1.77 *sin90

B=0.0144 tesla

6 0

3 years ago

What is perfect machine

Fittoniya [83]

Answer:

Explanation:

A machine is which no part of the work done on the machine is wasted, is called an ideal or perfect machine

5 0

3 years ago

Read 2 more answers