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3 years ago

A skater slides across the ice with an initial velocity of 5.0 m/s. She slows 10 points

Physics

1 answer:

zvonat [6]3 years ago

7 0

Explanation:

Given that,

The initial velocity of a skater is, u = 5 m/s

She slows to a velocity of 2 m/s over a distance of 20 m.

We can find the acceleration of skater. It is equal to the rate of change of velocity. So, it can be calculated using third equation of motion as follows :

$v^2-u^2=2as$

a = acceleration

$a=\dfrac{v^2-u^2}{2s}\\\\a=\dfrac{(2)^2-(5)^2}{2\times 20}\\\\a=-0.525\ m/s^2$

So, her acceleration is $0.525\ m/s^2$ and she is deaccelerating. Also, her initial velocity is given i.e. 5 m/s.

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6–23 an automobile engine consumes fuel at a rate of 22 l/h and delivers 55 kw of power to the wheels. if the fuel has a heating

Anna007 [38]

Explanation & answer:

Given:

Fuel consumption, C = 22 L/h

Specific gravity = 0.8

output power, P = 55 kW

heating value, H = 44,000 kJ/kg

Solution:

Calculate energy intake

E = C*P*H

= (22 L/h) / (3600 s/h) * (1000 mL/L) * (0.8 g/mL) * (44000 kJ/kg)

= (22/3600)*1000*0.8*44000 j/s

= 215111.1 j/s

Calculate output power

P = 55 kW

= 55000 j/s

Efficiency

= output / input

= P/E

=55000 / 215111.1

= 0.2557

= 25.6% to 1 decimal place.

8 0

3 years ago

MamaMia's Pizza purchases its pizza delivery boxes from a printing supplier. MamaMia's delivers on-average 200 pizzas each month

Ira Lisetskai [31]

Answer:

a) 138 units

b) 17 units

c) 17 units

d) Total Cost = $353.35

Explanation:

Given:

Average pizzas delivered = 200

Charge of inventory holding = 30% of cost

Lead time = 7 days

Now,

a) Economic Order Quantity = $\sqrt\frac{2\times\textup{Annual Demand}\times\textup{Cost per Order}}{\textup{Carrying cost}}$

also,

Annual Demand = 200 × 12 = 2400

Cost per Order = Cost of Box + Processing Costs

= 30 cents + $10

= $10.30

and, Carrying Cost = $\frac{\textup{Total Inventory Cost}}{\textup{total annual demand}}$

= $\frac{\textup{Total Cost per order}\times\textup{Annual demand}\times\frac{25}{100}}{\textup{Annual demand}}$

= $\frac{\$10.30\times2400}\times\frac{25}{100}}{2400}$

= $2.575

Therefore,

Economic Order Quantity = $\sqrt\frac{2\times\textup{2400}\times\textup{10.30}}{\textup{2.575}}$

= 138.56 ≈ 138 units

b) Reorder Point

= (average daily unit sales × the lead time in days) + safety stock

= ( $\frac{200}{30}\times7$

= 46.67 ≈ 47 units

c) Number of orders per year = $\frac{\textup{Annual Demand}}{\textup{Economic order quantity}}$

= $\frac{\textup{2400}}{\textup{138}}$

= 17.39 ≈ 17 units

d) Total Annual Cost (Total Inventory Cost)

= Ordering Cost + Holding Cost

Now,

The ordering Cost = Cost per Order × Total Number of orders per year

= $10.30 × 17

= $175.1

and,

Holding Cost = Average Inventory Held × Carrying Cost per unit

Average Inventory Held = $\frac{\textup{0+138}}{\textup{2}}$ = 69

Carrying Cost per unit = $2.575

Holding Cost = 69 × $2.575 =

$177.675

Therefore,

Total Cost = Ordering Cost + carrying cost

= $175.1 + $177.675 = $353.35

5 0

3 years ago

Read 2 more answers

The same amount of substance was added to four beakers of water. The treatments were placed in the chart.

vfiekz [6]

Answer: Solution W and Y solution have more solubility than X and Z

Solutions are homogeneous mixtures of two or more components. By uniform mix we mean that its structure and properties are the same in the whole mix. Generally, the component which is present in the largest quantity is known as solvent. Solvent determines the physical condition in which the solution exists. In addition to the solvent, one or more component present in the solution is called solutes. In this unit we will only consider binary solutions (i.e., with two components)

The structure of the solution can be described by expressing its concentration. The latter can either be expressed qualitatively or quantitatively. For example, in qualitatively we can say that the solution is diluted (i.e., relatively small amounts of solubility) or it is concentrated (i.e., relatively rarely sighs). But in real life such details may be very confusing and thus require a quantitative description of the solution. There are several ways that we can quantitatively describe the concentration of solutions. (i) Mass Percentage (W / W): The mass percentage of a component of the solution is defined as: mass of the component = mass of the component in the solution = 100 Total mass of the solution .For example, if by mass A solution is described by 10% glucose in water, it means that 10 grams of glucose dissolved in 90 grams of water, resulting in 100 grams of solution. The concentration described by a large percentage of the population is usually used in industrial chemical applications. For example, the commercial bleaching solution contains 3.62 mass percentages of sodium hypochlorite in water. (ii) Volume Percentage (V / V): Volume Percentage is defined as: Total Volume of Component Volume 100 (component) Volume% of Component

Explanation:

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2 years ago

On which date is the gravitational force between Earth and the moon the greatest?

Genrish500 [490]

The gravitational forces between the Earth and Moon are greatest when the two bodies are closest together. That happens every 27.32 days, when the Moon is at the perigee of its orbit.

Even if this happened at the same time in every orbit, the date would change, because there are not 27.32 days in a month.

But it doesn't happen at the same time in every orbit ... the Moon's perigee precesses around its orbit, on account of the gravitational forces toward the Earth, the Sun, Venus, Mars, and the other planets.

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3 years ago

Neglecting air resistance, what maximum height will be reached by an arrow launched straight upward with an initial speed of 35

tankabanditka [31]

The velocity at the maximum height will always be 0. Therefore, you will count your final velocity as 0, and your initial velocity as 35 m/s. Next, we know that the acceleration will be 9.8 m/s^2. How? Because the ball is thrown directly upward, and the only force acting on it will be the force of gravity pushing it back down.

The formula we use is h = (Vf^2 - Vi^2) / (2*-9.8m/s^2)

Plugging everything in, we have h = (0-1225)/(19.6) = 62.5 meters is the maximum height.

3 0

3 years ago