Kinetic energy is greatest when a roller coaster

1-A car moves toward east 12km is represented as A and it turns towards south 16km is represented as B. What is the resultant ve

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1. A-20 km south east

The car's displacement consists of two components into two different directions. Using a system of coordinates in which x represents the east direction and y represents the south direction, the two displacements are:

$d_x = 12 km$ east

$d_y = 16 km$ south

Since the two components are orthogonal to each other, we can find the resultant displacement by using Pythagorean's theorem:

$d=\sqrt{d_x^2+d_y^2}=\sqrt{(12 km)^2+(16 km)^2}=\sqrt{400}=20 km$

and the direction is between the two original directions, so south-east.

2. D. 10 m/s

First of all, we need to calculate the total time the stone took to hit the ground. Since the vertical distance covered is S = 78.4 m, and since the motion is an accelerated motion with constant acceleration g=9.8 m/s^2, we have

$S=\frac{1}{2}gt^2$

From which we find the total time of the fall, t:

$t=\sqrt{\frac{2S}{g}}=\sqrt{\frac{2(78.4 m)}{9.8 m/s^2}}=4 s$

Now we can consider the horizontal motion of the stone: we know that the stone travels for d = 40 m in a time of t = 4 s, therefore the horizontal velocity of the stone is

$v=\frac{d}{t}=\frac{40 m}{4 s}=10 m/s$

3. B=32.32 m

As in the previous problem, we have to calculate the total time it takes for the stone to reach the river first. Since the vertical distance covered is S = 20 m, we have

$t=\sqrt{\frac{2S}{g}}=\sqrt{\frac{2(20 m)}{9.8 m/s^2}}=2.0 s$

And since the stone is traveling horizontally at v = 16 m/s, the horizontal distance covered is

$d=vt=(16 m/s)(2 s)=32 m$

So, the closest answer is B.

5 0

3 years ago

A block rests on a ?at plate that executes vertical simple harmonic motion with a period of 0.58s.

SVETLANKA909090 [29]

Answer:

maximum amplitude = 0.08 m

Explanation:

Given that

Time period T= 0.58 s

acceleration of gravity g= 9.8 m/s²

We know that time period of simple harmonic motion given as

T = 2π/ω

0.58 = 2π/ω

ω = 10.83rad/s

ω=angular frequency

Lets take amplitude = A

The maximum acceleration given as

a= ω² A

The maximum acceleration should be equal to g ,then block does not separate

a= ω² A

9.8 = 10.83² A

A = 0.08m

maximum amplitude = 0.08 m

8 0

3 years ago

Read 2 more answers

I need help on ideas for a science project.. (highschool ideas)

Nana76 [90]

A research question that would complete the third question you need that are related to the first 2 questions which are:

“what type of masks help prevent fog on glasses when breathing?”
“does a mask’s material affect the level of fog on glasses as an effect of breathing?”

Would be: "Are there any available masks that could prevent fog on glasses that could be improved upon"?

This new research question would help you find out if there is an already existing mask that could be made better.

<h3>What is a Research Question?</h3>

This refers to "a question that a research project sets out to answer". and seeks to give answers to particular phenomena.

Hence, we can see that the new research question Would be: "Are there any available masks that could prevent fog on glasses that could be improved upon"?

This new research question would help you find out if there is an already existing mask that could be made better.

Read more about research questions here:

brainly.com/question/25257437

#SPJ1

8 0

1 year ago

8a. What is the equivalent resistance of the following circuit?

ollegr [7]

Answer: Take your pick

Explanation:

if they are all in parallel 1 /(1/100 + 1/300 + 1/50) = 30 Ω

if 50 is in parallel with 2 in series 1 / (1/(100 + 300) + 1/50) = 44.444...Ω

if 100 is in parallel with 2 in series 1 / (1/(50 + 300) + 1/100) = 77.777...Ω

if 300 is in parallel with 2 in series 1 / (1/(100 + 50) + 1/300) = 100 Ω

If 50 is in series with 2 in parallel 50 + 1/(1/100 + 1/300) = 125 Ω

If 100 is in series with 2 in parallel 100 + 1/(1/50 + 1/300) = 142.857...Ω

If 300 is in series with 2 in parallel 300 + 1/(1/50 + 1/100) = 333.333...Ω

If they are all in series 100 + 300 + 50 = 450 Ω

4 0

3 years ago

A battery does work on electric charges to bring them to a position of higher electric potential energy so that they can flow th

Ipatiy [6.2K]

(Missing question is: which of the following statements are true?)

a) A battery does work on electric charges to bring them to a position of higher electric potential energy so that they can flow through a circuit to a lower potential energy --> TRUE
That's true: the battery does the work to move the charges to one end of its terminal thus creating a potential difference between the two terminals. Then, when it is connected to the circuit, charges start to flow to the terminal at lower potential (through the circuit)

b) the potential difference between the terminals of a battery, when no current flows to an external circuit, is referred to as the terminal voltage --> FALSE
This is false: when no current flows, it is called e.m.f. (electromotive force)

c) the internal resistance of a battery decreases with decreasing temperature
--> TRUE
In fact, the dependence of a resistance with the temperature is:
 $R=R_0[1+\alpha (T-T_0)]$
with $\alpha$ being generally positive, therefore the value of the resistance is proportional to T, and when T decreases, R decreases as well.

d) a battery is a device that produces electricity by transforming chemical energy into electrical energy --> TRUE
That's true: a battery uses chemical reactions to create a potential difference between the two terminals that can be exploited to make charges flowing through a circuit.

7 0

3 years ago