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3 years ago

How can friction help you in your daily life?

2 answers:

6 0

Answer: friction can help you in many ways such as when you hit the brakes on your car or when you are washing your face

Explanation:

friction happens in just about everything you do

skad [1K]3 years ago

5 0

Friction help us us maintain our stability and prevents us from slipping. Friction also works the same way with cars and vehicles preventing them from skidding and helping them stop when the brakes are applied.

This is maybe too little.

Hope this helps though! C:

You might be interested in

Which of these has the least chemical energy?

madreJ [45]

The answer is option D a gallon of gasoline.

Explanation:

A gallon of gasoline has the least chemical energy. The energy content of gallon of gasoline is about 132,000 Btu. The gasoline produced is equivalent in energy terms to 4 kilowatt hours.

Gasoline has chemical potential energy stored in chemical bonds. Gasoline is called as gas or petrol, mixture of volatile, flammable liquid hydrocarbons are used as fuel for internal- combustion engines. It is used as solvent for oils and fats.

Gasoline gallon equivalent is the alternative fuel taken to equal the energy content of one liquid gallon of gasoline.

4 0

3 years ago

A merry-go-round with a a radius of R = 1.9 m and moment of inertia I = 209 kg-m2 is spinning with an initial angular speed of ω

RideAnS [48]

Answer:

340.67 kgm²/s

Explanation:

R = Radius of merry-go-round = 1.9 m

I = Moment of inertia = 209 kgm²

$\omega_i$ = Initial angular velocity = 1.63 rad/s

m = Mass of person = 73 kg

v = Velocity = 4.8 m/s

Initial angular momentum is given by

$L=I\omega_i\\\Rightarrow L=209\times 1.63\\\Rightarrow L=340.67\ kgm^2/s$

The initial angular momentum of the merry-go-round is 340.67 kgm²/s

8 0

3 years ago

Help me please, need more assistance

Dmitrij [34]

Explanation:

12) q = mCΔT

125,600 J = (500 g) (4.184 J/g/K) (T − 22°C)

T = 82.0°C

13) Solving for ΔT:

ΔT = q / (mC)

a) ΔT = 1 kJ / (0.4 kg × 0.45 kJ/kg/K) = 5.56°C

b) ΔT = 2 kJ / (0.4 kg × 0.45 kJ/kg/K) = 11.1°C

c) ΔT = 2 kJ / (0.8 kg × 0.45 kJ/kg/K) = 5.56°C

d) ΔT = 1 kJ / (0.4 kg × 0.90 kJ/kg/K) = 2.78°C

e) ΔT = 2 kJ / (0.4 kg × 0.90 kJ/kg/K) = 5.56°C

f) ΔT = 2 kJ / (0.8 kg × 0.90 kJ/kg/K) = 2.78°C

14) q = mCΔT

q = (2000 mL × 1 g/mL) (4.184 J/g/K) (80°C − 20°C)

q = 502,000 J

20) q = mCΔT

q = (2000 g) (4.184 J/g/K) (100°C − 15°C) + (400 g) (0.9 J/g/K) (100°C − 15°C)

q = 742,000 J

24) q = mCΔT

q = (0.10 g) (0.14 J/g/K) (8.5°C − 15°C)

q = -0.091 J

6 0

3 years ago

Practice: The speed of sound at sea level is normally about 340 m/s. A car honks its horn as it drives toward an observer. The f

stepan [7]

Answer:

25.5 m/s

Explanation:

The Doppler effect occurs when there is relative motion between a source of a wave and an observer. In such situation, there is a shift in the apparent frequency of the wave perceived by the observer.

The formula that gives the apparent frequency perceived by the observer is:

$f'=\frac{v\pm v_o}{v\pm v_s}f$

where

f is the real frequency of the wave

f' is the apparent frequency of the wave

v is the speed of the wave

$v_s$ is the velocity of the source (negative if the source is moving towards the observer, positive otherwise)

$v_o$ is the velocity of the observer (positive if the observer is moving towards the source, negative otherwise)

In this problem:

v = 340 m/s is the speed of sound

f = 800 Hz is the frequency of the horn

f' = 860 Hz is the apparent frequency

$v_o=0$ (the observer is at rest)

Re-arranging the equation for $v_s$ , we can find the velocity of the horn and the driver:

$f'=\frac{v}{v-v_s}f\\(v-v_s)f'=vf\\vf'-v_sf'=vf\\v_s=v\frac{f'-f}{f'}=(340)\frac{860-800}{860}=25.5 m/s$

So, 25.5 m/s towards the observer.

3 0

3 years ago

The cells lie odjacent to the sieve tubes

nignag [31]

Answer:

<h2>Almost always adjacent to nucleus containing companion cells, which have been produced as sister cells with the sieve elements from the same mother cell. </h2>

4 0

3 years ago