<span>A bike is compound machine.This means that it is made up of a bunch of different simple machines. Screws are used to hold the pieces together. The wheel of a bicycle is a wheel and axle. The pedals are also examples of this simple machine. The pedals are attached to a lever that turns a pulley.</span>

6 0

3 years ago

Read 2 more answers

Which two phrases best describe cells?

guapka [62]

<h3><u>Answer;</u></h3>

Make up tissues
The simplest level of organization of life

<h3><u>Explanation;</u></h3>

<em><u>Cells are the smallest part of an organism that can carry out all of life functions. They are the basic functional unit of all living organisms.</u></em>
According to cell theory all living things are composed of cells, cells are the basic units of structure and function in living things, and new cells are produced from existing cells
<em><u>A group of cells make up tissues. Tissues are a group of cells that are specialized to carry out specific functions in plants and animal bodies. </u></em>

3 0

3 years ago

A wire of length 6cm makes an angle of 20° with a 3 mT

Crazy boy [7]

Answer:

Approximately $7.3 \times 10^{-3}\; \rm A$ (approximately $7.3\; \rm mA$ ) assuming that the magnetic field and the wire are both horizontal.

Explanation:

Let $\theta$ denote the angle between the wire and the magnetic field.

Let $B$ denote the magnitude of the magnetic field.

Let $l$ denote the length of the wire.

Let $I$ denote the current in this wire.

The magnetic force on the wire would be:

$F = B \cdot l \cdot I \cdot \sin(\theta)$ .

Because of the $\sin(\theta)$ term, the magnetic force on the wire is maximized when the wire is perpendicular to the magnetic field (such that the angle between them is $90^\circ$ .)

In this question:

$\theta = 20^\circ$ (or, equivalently, $(\pi / 9)$ radians, if the calculator is in radian mode.)
$B = 3\; \rm mT = 3 \times 10^{-3}\; \rm T$ .
$l = 6\; \rm cm = 6 \times 10^{-2}\;\rm m$ .
$F = 1.5\times 10^{-4}\; \rm N$ .

Rearrange the equation $F = l \cdot I \cdot \sin(\theta)$ to find an expression for $I$ , the current in this wire.

$\begin{aligned} I &= \frac{F}{l \cdot \sin(\theta)} \\ &= \frac{3\times 10^{-3}\; \rm T}{6 \times 10^{-2}\; \rm m \times \sin \left(20^{\circ}\right)} \\ &\approx 7.3 \times 10^{-3}\; \rm A = 7.3 \; \rm mA\end{aligned}$ .

5 0

2 years ago