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2 years ago

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A car starts from rest and travels for t1 seconds with a uniform acceleration a1. The driver then applies the brakes, causing a

uniform acceleration a2. If the brakes are applied for t2 seconds, determine the following. Answers are in terms of the variables a1, a2, t1, and t2. (a) How fast is the car going just before the beginning of the braking period?

1 answer:

Triss [41]2 years ago

5 0

Explanation:

It is given that,

Initially the car is at rest and travels for t₁ seconds with a uniform acceleration a₁. The driver then applies the brakes, causing a uniform acceleration a₂, If the brakes are applied for t₂ seconds.

We need to find the speed of the car just before the beginning of the braking period.

Using the formula of acceleration. It is given by :

$a_1=\dfrac{v-u}{t_1}$

u = 0

$v=a_1\times t_1$

So, just before the beginning of the braking period the speed of the car is $a_1\times t_1$ . Hence, this is the required solution.

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3 years ago

Thermopane window is constructed, using two layers of glass 4.0 mm thick, separated by an air space of 5.0 mm.

Bond [772]

To solve this problem it is necessary to apply the concepts related to rate of thermal conduction

$\frac{Q}{t} = \frac{kA\Delta T}{d}$

The letter Q represents the amount of heat transferred in a time t, k is the thermal conductivity constant for the material, A is the cross sectional area of the material transferring heat, $\Delta T$ , T is the difference in temperature between one side of the material and the other, and d is the thickness of the material.

The change made between glass and air would be determined by:

$(\frac{Q}{t})_{glass} = (\frac{Q}{t})_{air}$

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2 years ago

The coil of a generator has a radius of 0.14 m. When this coil is unwound, the wire from which it is made has a length of 10.0 m

adell [148]

Answer:

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