Answer:
The work done by friction was 
Explanation:
Given that,
Mass of car = 1000 kg
Initial speed of car =108 km/h =30 m/s
When the car is stop by brakes.
Then, final speed of car will be zero.
We need to calculate the work done by friction
Using formula of work done



Put the value of m and v



Hence, The work done by friction was 
From the given equation we can deduce what changes will occur if the frequency of the sound is doubled
V= f (λ)
Speed = frequency. Wavelength
When the frequency is doubled, speed will not change. Because speed depends on factors like temperature, air pressure, density of the gas. Since all these factors are unchanged thus speed will remain unchanged
Frequency is the number of waves produced per second. Frequency and wavelength are inversely proportional .Thus, if the frequency is doubled the wavelength would be halved.
An example is when u rub your pen on your hair hard that is friction
Answer:
Motors convert electrical energy into mechanical energy
Explanation:
A motor uses electrical energy to create mechanical energy by creating magnetic fields causing the motor to spin. A generator is the opposite and converts mechanical into electrical by spinning a motor in a magnetic field.
The maximum speed is 10.4 m/s
Explanation:
For a body in uniform circular motion, the centripetal acceleration is given by:

where
v is the linear speed
r is the radius of the circular path
In this problem, we have the following data:
- The maximum centripetal acceleration must be

where
is the acceleration of gravity. Substituting,

- The radius of the turn is
r = 10 m
Therefore, we can re-arrange the equation to solve for v, to find the maximum speed the ride can go at:

Learn more about centripetal acceleration:
brainly.com/question/2562955
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