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3 years ago

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A group of 3 children and 2 adults pay a total of $120 to take a karate class. A group of 5 children and 1 adult take the same k

arate class for $95.

1 answer:

sleet_krkn [62]3 years ago

8 0

Answer:

215

Step-by-step explanation:

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In a circus performance, a monkey is strapped to a sled and both are given an initial speed of 3.0 m/s up a 22.0° inclined track

Aloiza [94]

Answer:

Approximately $0.31\; \rm m$ , assuming that $g = 9.81\; \rm N \cdot kg^{-1}$ .

Step-by-step explanation:

Initial kinetic energy of the sled and its passenger:

$\begin{aligned}\text{KE} &= \frac{1}{2}\, m \cdot v^{2} \\ &= \frac{1}{2} \times 14\; \rm kg \times (3.0\; \rm m\cdot s^{-1})^{2} \\ &= 63\; \rm J\end{aligned}$ .

Weight of the slide:

$\begin{aligned}W &= m \cdot g \\ &= 14\; \rm kg \times 9.81\; \rm N \cdot kg^{-1} \\ &\approx 137\; \rm N\end{aligned}$ .

Normal force between the sled and the slope:

$\begin{aligned}F_{\rm N} &= W\cdot \cos(22^{\circ}) \\ &\approx 137\; \rm N \times \cos(22^{\circ}) \\ &\approx 127\; \rm N\end{aligned}$ .

Calculate the kinetic friction between the sled and the slope:

$\begin{aligned} f &= \mu_{k} \cdot F_{\rm N} \\ &\approx 0.20\times 127\; \rm N \\ &\approx 25.5\; \rm N\end{aligned}$ .

Assume that the sled and its passenger has reached a height of $h$ meters relative to the base of the slope.

Gain in gravitational potential energy:

$\begin{aligned}\text{GPE} &= m \cdot g \cdot (h\; {\rm m}) \\ &\approx 14\; {\rm kg} \times 9.81\; {\rm N \cdot kg^{-1}} \times h\; {\rm m} \\ & \approx (137\, h)\; {\rm J} \end{aligned}$ .

Distance travelled along the slope:

$\begin{aligned}x &= \frac{h}{\sin(22^{\circ})} \\ &\approx \frac{h\; \rm m}{0.375}\end{aligned}$ .

The energy lost to friction (same as the opposite of the amount of work that friction did on this sled) would be:

$\begin{aligned} & - (-x)\, f \\ = \; & x \cdot f \\ \approx \; & \frac{h\; {\rm m}}{0.375}\times 25.5\; {\rm N} \\ \approx\; & (68.1\, h)\; {\rm J}\end{aligned}$ .

In other words, the sled and its passenger would have lost (approximately) $((137 + 68.1)\, h)\; {\rm J}$ of energy when it is at a height of $h\; {\rm m}$ .

The initial amount of energy that the sled and its passenger possessed was $\text{KE} = 63\; {\rm J}$ . All that much energy would have been converted when the sled is at its maximum height. Therefore, when $h\; {\rm m}$ is the maximum height of the sled, the following equation would hold.

$((137 + 68.1)\, h)\; {\rm J} = 63\; {\rm J}$ .

Solve for $h$ :

$(137 + 68.1)\, h = 63$ .

$\begin{aligned} h &= \frac{63}{137 + 68.1} \approx 0.31\; \rm m\end{aligned}$ .

Therefore, the maximum height that this sled would reach would be approximately $0.31\; \rm m$ .

7 0

3 years ago

Is the relationship shown by the data linear? x -9, -5, -1, 3 y -2,-7,-12, -17

Temka [501]

x y
------ -----
-9 -2
-5 -7
-1 -12
3 -17

ur x's all have a difference of 4, and ur y's all have a difference of -5...so yes, this is linear with a slope of (-7+2) / (-5 + 9) = -5/4

5 0

3 years ago

Using the numbers 5, 8, and 24, create a problem using no more than 4 operations (adding, subtracting, multiplication, division,

nalin [4]

<span>√(5*8*24) or anything along those lines, you can switch the numbers around , it wont matter</span>

3 0

3 years ago

HELP ME I'M STUCK!!!! PLEASE AND THANK YOU!!!!

Darya [45]

Answer: 1/8

Step-by-step explanation: The sample space are all of the different outcomes an event can lead to. The H and T combinations at the bottom are all of the different outcomes. I think the probability of getting 3 tails for the coins (or TTT) is 1/8. This is because there are 24 total outcomes (HHH, HHT, HTH, HTT, THH, THT, TTH, TTT). There is 3/24 TTTs (also, 1/8 if you count the groups/simplify). Therefore, it is 1/8. Hope this helps!

3 0

3 years ago

A set of gulf clubs is on sale for $150, which is 70% off of its original price. What was the original price of the gulf clubs

Alika [10]

Answer: 500$

Step-by-step explanation: 150 is 70% off the ORIGINAL price, so 150 is actually 30% off. Divide everything by 3 and you get 50$ = 10%. Multiple 50 by 10 and you get 500, your answer.

8 0

3 years ago