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3 years ago

Hello!

Physics

1 answer:

34kurt3 years ago

8 0

Iodine-131 has a half life of 8 days, so half of it is gone every 8 days.
10 grams of iodine-131 is left for 24 days.
At 8 days: 10/2=5 grams left
At 16 days: 5/2=2.5 grams left
At 24 days: 2.5/2=1.25 grams left.
**
Your mistake is that you stopped at 16 days.

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It has been observed that electrical connectors manufactured by Jolt Electrical Supply Company last an average of 18.2 months an

Viktor [21]

Answer:

Jolt can expect to replace 160 units.

Explanation:

given data:

standard deviation 1.7

average lfe of connectors = 18.2 months

number of connectors = 5000

$z(19) = \frac{(19-18.2)}{1.7}$

z(19) = 0.4706

P(x< 19) = P(z< 0.4706)

P(x< 19) = 0.6810 from z table

therefore 68.1% fails within 19 months.

hence 0.3190 {100-68.1} will fail during that period.

number of unit of Jolt that need to be replace, on average is 0.319*500 = 160 units.

7 0

3 years ago

Qué ocurre con el espectro cuando se interpone el celofán de colores?

Travka [436]

Answer: You will only see the color that cellophane lets through

Explanation:

Let's begin by the fact the whole electromagnetic spectrum is known as "white light", which is composed by a range of colors (wavelengths).

Now, if we have a source with white light (the Sun, for example) and we interpose a cellophane of any color (let's choose red), this cellophane will act as a filter and will only let pass the color of the cellophane.

This is because the filter will absorb the other colors of the spectrum.

3 0

3 years ago

In designing buildings to be erected in an area prone to earthquakes, what are the things that you need to consider?

il63 [147K]

Answer:

In an earthquake prone area, the things that are needed to be considered for the buildings to stand constant and no cause of damages are as follows-

The foundation of the building must be made strong, using large amount of concretes so that it can hold the entire load of the building.

The pillars of the buildings are also should be firmed, rigid, strong and thick.

The buildings are needed to be construct in such a way that during any seismic event, the forces can be redistributed easily through the body of the building without causing any damage.

The buildings must be overall comprised of holding high strength and stiffness.

6 0

3 years ago

Let the masses of blocks A and B be 4.50 kg and 2.00 kg , respectively, the moment of inertia of the wheel about its axis be 0.4

Free_Kalibri [48]

Answer:

Accelerations of both the sides is 0.6125 $m/s^{2}$ , A moves downwards whereas B moves upwards.

$\alpha$ =6.125 rad/ $s^{2}$

Tension on side A = 4.5 × g= 44.1 m/ $s^{2}$

Tension on side B= 2.0 × g= 19.6 m/ $s^{2}$

Explanation:

As both, the blocks A and B are attached due to the constraint they can only possess a single acceleration a.

Observe the figure attached, let the tension with Block A be $T_{2}$ and the tension attached with Block B be $T_{1}$ .

Tensions will be only be due to the weight of the blocks as no other force is present.

$T_{2}$ = 4.5 × g= 44.1 m/ $s^{2}$

$T_{1}$ = 2.0 × g= 19.6 m/ $s^{2}$

Now, lets make a torque equation about the center of the wheel and find the alpha

$T_{2}$ ×R- $T_{1}$ ×R= MI( Moment of Inertia of Wheel)× Alpha

where, R= Radius of the wheel=0.100m and

Alpha( $\alpha$ )= Angular acceleration of the wheel

MI of the wheel= 0.400 kg/ $m^{2}$

$(44.1-19.6)R=0.400\alpha$

$\alpha = \frac{24.5 * 0.100}{0.400}$

$\alpha$ =6.125 rad/ $s^{2}$

Acceleration = R × $\alpha$

= 0.1 * 6.125

=0.6125 $m/s^{2}$

Accelerations of both the sides is 0.6125 $m/s^{2}$ , A moves downwards whereas B moves upwards.

7 0

3 years ago

Lab: Equivalent Resistance of Series and Parallel Circuits

Aleonysh [2.5K]

Answer:

Since there is only one path for the charges to flow through, the current is the same through each resistor. The equivalent resistance of a set of resistors in a series connection is equal to the algebraic sum of the individual resistances.

4 0

3 years ago