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A biker pedals hard to ride his bike to the top of a 44 m hill. He decides to let his bike coast down the hill, and is having so

Vanyuwa [196]

The biker's speed at the top of the second hill is 25.8 m/s

Explanation:

The problem can be solve by applying the law of conservation of energy. In absence of frictional forces, the total mechanical energy of the bike (the sum of potential energy + kinetic energy) must be conserved. So we can write:

$U_i +K_i = U_f + K_f$

where

$U_i$ is the initial potential energy at the top of the first hill

$K_i$ is the initial kinetic energy at the top of the first hill

$U_f$ is the final potential energy at the top of the second hill

$K_f$ is the final kinetic energy at the top of the second hill

We can rewrite the equation as:

$mgh_i + \frac{1}{2}mu^2 = mgh_f + \frac{1}{2}mv^2$

where:

m is the mass of the bike

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

$h_i = 44 m$ is the height of the first hill

u = 0 m/s is the speed at the top of the first hill

$h_f = 10 m$ is the height of the second hill

v is the speed at the top of the second hill

And solving for v, we find:

$mgh_i = mgh_f + \frac{1}{2}mv^2\\v^2=\sqrt{2g(h_i-h_f)}=\sqrt{2(9.8)(44-10)}=25.8 m/s$

Learn more about kinetic energy and potential energy:

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7 0

3 years ago

A beaker of boiling water stops boiling and eventually reaches room

solniwko [45]

Answer:

C

Explanation:

I just took the quiz

8 0

3 years ago

Read 2 more answers

Driving home from school one day, you spot a ball rolling out into the street (Figure 5-21). You brake for 1.20 s, slowing your

frosja888 [35]

A ) v = v o + a t ( the acceleration will be negative )
9.50 = 16.0 + a * 1.2
a * 1.2 = -16.0 + 9.50
a * 1.2 = - 6.5
a = - 6.5 : 1.2
a = - 5.4167 m/s²
F = m * a = 950 kg * 5.4167 m/s²
F = 5,145.8 N ( the average force exerted on a car during braking )
b ) d = v o - a t² / 2
d = 16.0 * 1.2 - ( 5.4167 * 1.2² / 2 ) =
= 19.20 - 3.90 = 15.30 m

7 0

3 years ago

"If you double the wavelength of a wave on a particular string", what happens to the wave speed v and the frequency f ? (i) v do

nadezda [96]

Answer:

v doubles and f is unchanged

Explanation:

According to the formula v = f¶

Where v is the velocity of the wave

f is the frequency

¶ is the wavelength

Velocity is directly proportional to wavelength. Direct proportionality shows that increase in velocity will cause an increase in the wavelength and decrease in velocity will also cause a decrease in wavelength with the frequency not changing since the velocity and wavelength are both increasing and decreasing at the same rate.

According to the question, if the wavelength is doubled, the velocity (v) will also double while the frequency (f) remains unchanged.

5 0

3 years ago

Read 2 more answers

On a nice summer day,Kim takes her niece Madison for a walk in her stroller.If they start from rest and accelerate at a rate of

11111nata11111 [884]

2.5m/s

Explanation:

Given parameters:

Initial velocity = 0m/s

Acceleration = 0.5m/s²

time of travel = 5s

Solution:

Final velocity = ?

Solution:

Acceleration can be defined as the change in velocity with time:

Acceleration = $\frac{Final velocity - Initial velocity}{time}$

From the equation above, the unknown is final velocity:

Final velocity - initial velocity = Acceleration x time

since initial velocity = 0

Final velocity = 0.5 x 5 = 2.5m/s

Learn more:

Acceleration brainly.com/question/3820012

#learnwithBrainly

6 0

3 years ago