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2 years ago

a car advertisement States that a certain car can accelerate from rest to70km/h in 7seconds find the car's average acceleration

Physics

1 answer:

Aneli [31]2 years ago

8 0

Answer:

Acceleration is 2.78 m/s²

Explanation:

Since the car is from rest, initial velocity, u is zero.

from first newton's equation of motion:

${ \bf{v = u + at}} \\$

v is final velocity

u is initial velocity

a is acceleration

t is time

70 km/h is (70 × 1000 ÷ 3600) m/s = 19.44 m/s

${ \sf{19.44 = 0 + (a \times 7)}} \\ { \sf{7a = 19.44 }} \\ { \sf{a = 2.78 \: {ms}^{ - 2} }}$

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Which refers to the amount of heat required to change the temperature of 1 gram of a substance by 1°C and is related to the chem

timama [110]

Answer:

Specific heat

Explanation:

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2 years ago

The substances referenced in the table are being considered for use in cooking materials. Since the materials must be melted dur

frutty [35]

Brass requires more energy than silver

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Aluminum requires more energy than brass

Explanation:

The specific heat capacity of a substance indicates the amount of heat energy required to raise 1 kg of that substance by 1 degree in temperature.

Mathematically:

$C=\frac{Q}{m\Delta T}$

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Brass requires more energy than silver

Aluminum requires more energy than copper

Aluminum requires more energy than brass

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brainly.com/question/3032746

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2 years ago

When a mass of 0.350 kg is attached to a vertical spring and lowered slowly, the spring stretches 12.0 cm. The mass is now displ

pantera1 [17]

Answer:

The period is $T = 0.700 \ s$

Explanation:

From the question we are told that

The mass is $m = 0.350 \ kg$

The extension of the spring is $x = 12.0 \ cm = 0.12 \ m$

The spring constant for this is mathematically represented as

$k = \frac{F}{x}$

Where F is the force on the spring which is mathematically evaluated as

$F = mg = 0.350 * 9.8$

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$k = \frac{3.43 }{ 0.12}$

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$T = 2 \pi \sqrt{\frac{m}{k} }$

substituting values

$T = 2 * 3.142* \sqrt{\frac{0.35 }{28.583} }$

$T = 0.700 \ s$

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3 years ago

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Dennis_Churaev [7]

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a car advertisement States that a certain car can accelerate from rest to70km/h in 7seconds find the car's average acceleration​

a car advertisement States that a certain car can accelerate from rest to70km/h in 7seconds find the car's average acceleration