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3 years ago

How can I change my Brainly username?

2 answers:

8 0

In the current brainly version, unfortunately you could not change your username.

The only way is to create a new account, but of course all of your points will be gone

mina [271]3 years ago

4 0

Answer:

Hi there! For changing your username you can contact to administrator of the site. If you are using app then go to message option. Then search "rishilaugh" then you can message him.

Explanation:

You might be interested in

What happens to a circuit's resistance (R), voltage (V), and current (1) when

hammer [34]

Answer:

R increases

V is constant

I decreases

Explanation:

The resistance of a wire is given by the following formula:

$R = \frac{(Resistivity)(L)}{A}$

It is clear from this formula that resistance is directly proportional to the length of wire. So, when length of wire is increased, the resistance of circuit increases.

The voltage in the circuit will be constant as the voltage source remains same and it is not changed.

Now, we can use Ohm Law:

V = IR

at constant V:

I ∝ 1/R

it means that current is inversely proportional to resistance. Hence, the increase of resistance causes the current in circuit to decrease.

Therefore, the correct option will be:

D.

R increases

V is constant

I decreases

6 0

2 years ago

If you do 1500 J of work hoisting a 20 kg bale of hay , to what height did you lift it

strojnjashka [21]

Explanation:

W = PE

W = mgh

1500 J = (20 kg) (9.8 m/s²) h

h = 7.65 m

Round as needed.

4 0

3 years ago

A man walks along a straight path at a speed of 4 ft/s. A searchlight is located on the ground 6 ft from the path and is kept fo

BARSIC [14]

We are given that,

$\frac{dx}{dt} = 4ft/s$

We need to find $\frac{d\theta}{dt}$ when $x=8ft$

The equation that relates x and $\theta$ can be written as,

$\frac{x}{6} tan\theta$

$x = 6tan\theta$

Differentiating each side with respect to t, we get,

$\frac{dx}{dt} = \frac{dx}{d\theta} \cdot \frac{d\theta}{dt}$

$\frac{dx}{dt} = (6sec^2\theta)\cdot \frac{d\theta}{dt}$

$\frac{d\theta}{dt} = \frac{1}{6sec^2\theta} \cdot \frac{dx}{dt}$

Replacing the value of the velocity

$\frac{d\theta}{dt} = \frac{1}{6} cos^2\theta (4)^2$

$\frac{d\theta}{dt} = \frac{8}{3} cos^2\theta$

The value of $cos \theta$ could be found if we know the length of the beam. With this value the equation can be approximated to the relationship between the sides of the triangle that is being formed in order to obtain the numerical value. If this relation is known for the value of x = 6ft, the mathematical relation is obtained. I will add a numerical example (although the answer would end in the previous point) If the length of the beam was 10, then we would have to