Plzzzzzzz help me<br> 15 pt for 1st 10 for 2nd

What is not a reason correlations are useful?

Vikki [24]

<span>Correlations allow you to make inferences.</span>

4 0

3 years ago

Suppose you walk 11 m in a direction exactly 24° south of west then you walk 21 m in a direction exactly 39° west of north. 1) H

DENIUS [597]

Answer:

(1) 42.94 m

(2) $16.02^\circ$

Explanation:

Let us first draw a figure, for the given question as below:

In the figure, we assume that the person starts walking from point A to travel 11 m exactly $24^\circ$ south of west to point B and from there, it walks 21 m exactly $39^\circ$ west of north to reach point C.

Let us first write the two displacements in the vector form:

$\vec{AB} = (-11\cos 24^\circ\ \hat{i}-11\sin 24^\circ\ \hat{j})\ m =(-10.05\ \hat{i}-4.47\ \hat{j})\ m\\\vec{BC} = (-21\sin 39^\circ\ \hat{i}+21\cos 39^\circ\ \hat{j})\ m =(-31.22\ \hat{i}+16.32\ \hat{j})\ m$

Now, the vector sum of both these vectors will give us displacement vector from point A to point C.

$\vec{AC}=\vec{AB}+\vec{BC}\\\Rightarrow \vec{AC}=(-10.05\ \hat{i}-4.47\ \hat{j})\ m+(-31.22\ \hat{i}+16.32\ \hat{j})\ m\\\Rightarrow \vec{AC}=(-41.25\ \hat{i}+11.85\ \hat{j})\ m$

Part (1):

the magnitude of the shortest displacement from the starting point A to point the final position C is given by:

$AC=\sqrt{(-41.25)^2+(11.85)^2}\ m= 42.94\ m$

Part (2):

As the vector AC is coordinates lie in the third quadrant of the cartesian vector plane whose angle with the west will be positive in the north direction.

The angle of the shortest line connecting the starting point and the final position measured north of west is given by:

$\theta = \tan^{-1}(\dfrac{11.85}{41.27})\\\Rightarrow \theta = 16.02^\circ$

4 0

3 years ago

A 75-turn coil with a diameter of 6.00 cm is placed in a constant, uniform magnetic field of 1.00 T directed perpendicular to th

kolezko [41]

Answer:

The induced emf in the coil at the t = 5s is 6.363 mV

Explanation:

Given;

number of turns = 75

diameter of the coil = 6 cm

magnetic field strength = 1 T

new magnetic field strength = 1.30 T at t = 10.0 s

$Area \ of \ coil = \frac{\pi d^2}{4} = \frac{\pi *0.06^2}{4} = 0.002828 \ m^2$

$E.M.F = \frac{NA* \delta B}{\delta t}$

Between 0 to 5 s, Induced emf is given as;

$E.M.F = \frac{75*0.002828*(B_5-1)}{5}$

Between 5 to 10 s, Induced emf is given as;

$E.M.F = \frac{75*0.002828*(1.3-B_5)}{5}$

Since the field increased at a uniform rate until it reaches 1.30 T at t = 10.0 s, the induced emf will also increase in uniform rate. And equal time interval will generate same increase in field strength.

B₅ -1 = 1.3 - B₅

2B₅ = 2.3

B₅ = 1.15 T

Thus, magnetic field at t = 5 is 1.15 T

$E.M.F = \frac{75*0.002828*(1.3-1.15)}{5} = 6.363 \ mV$

Therefore, the induced emf in the coil at the t = 5s is 6.363 mV

7 0

3 years ago

Which best describes the meaning of the stayement “if A , then B”

Darya [45]

Answer:

A statement of the form “If A, then B” asserts that if A is true, then B must be true also. If the statement “If A, then B” is true, you can regard it as a promise that whenever the A is true, then B is true also.

I HOPE IT'S HELP.......

7 0

3 years ago

A simple circuit has a 12.0V12.0V battery and three resistors of 6.0Ω6.0Ω connected in parallel. If the current through the batt

Umnica [9.8K]

Answer:

The internal resistance of the battery is 1.0 Ω.

Explanation:

Given that,

Voltage = 12,0 V

Resistance of each resistor = 6.0 Ω

Current = 4.0 A