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2 years ago

A car has a kinetic energy of 103kJ.

Physics

1 answer:

sergij07 [2.7K]2 years ago

5 0

Answer: 1200kg

Explanation:

KE = (1/2)mv^2

103kJ = 103000J

103000J = (1/2) * m * (13.1m/s)^2

Solve for m

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Which statement is true for a car that first goes around a curve of radius r at a constant speed v, and then goes around the sam

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Centripetal force is equal to (mv^2)/r
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3 years ago

A silver tea spoon is placed in a cup filled with hot tea. After some time, the exposed end of the spoon becomes hot even withou

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Answer:

As atoms in the spoon vibrates about their equilibrium positions and transfer energy form one end to other end. This process is called conduction.

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2 years ago

Curtis, a student in our class, makes the following statement: The puck reached a slightly higher location on the ramp than I pr

Sindrei [870]

Answer and Explanation: No, the explanation is not plausible. The puck sliding on the ice is an example of the Principle of Conservation of Energy, which can be enunciated as "total energy of a system is constant. It can be changed or transferred but the total is always the same".

When a player hit the pluck, it starts to move, gaining kinetic energy (K). As it goes up a ramp, kinetic energy decreases and potential energy (P) increases until it reaches its maximum. When potential energy is maximum, kinetic energy is zero and vice-versa.

So, at the beginning of the movement the puck only has kinetic energy. At the end, it gains potential energy until its maximum.

The representation is as followed:

$K_{i}+P_{i}=K_{f}+P_{f}$

$K_{i}+0=0+P_{f}$

$\frac{1}{2}mv^{2} = mgh$

As we noticed, mass of the object can be cancelled from the equation, making height be:

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2 years ago

Which one of the following statements concerning emf is true?

Andrej [43]

Answer:

C) Emf is the force exerted on a single charge to move it from one terminal to the other of an emf device.

Explanation:

Electromotive force, abbreviation E or emf, electrical energy per unit supplied from an energy source, such as an electrical generator or a battery. In the engine or battery, electricity is transformed from one source to another as the device works on the electrical charge that is passed within itself.

In physics it is defined as Work done by a cell or battery in moving a unit charge from its one terminal to the other, against the potential.

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3 years ago

You are working out on a rowing machine. Each time you pull the rowing bar (which simulates the oars) toward you, it moves a dis

uranmaximum [27]

Answer:

The magnitude of force exerted on the handle is 108.73 N

Explanation:

To determine the magnitude of force exerted, we will use the formula relating Power and Force.

Power is the rate at which work is done. Power can be calculated from the formula

Power = Work / Time

But, Work = Force × Distance

Hence,

Power is given by the formula

$P = \frac{F \times s}{t}$

Where P is the Power

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s is the distance

and t is the time

From $P = \frac{F \times s}{t}$ ,

Then we can write that

$F = \frac{P \times t}{s}$

From the question,

Distance, s = 1.1 m

Time, t = 1.3 s

Power, P = 92 W

Putting these values into the formula, we get

$F = \frac{92 \times 1.3}{1.1}$

$F = \frac{119.6}{1.1}$

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Hence, the magnitude of force exerted on the handle is 108.73 N.

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2 years ago