All categories

3 years ago

Question 1 of 15

Physics

1 answer:

stepan [7]3 years ago

8 0

Answer:

significant

Explanation:

The digits in a measurement that are considered significant are all of those digits that represent marked calibrations on the measuring device plus one additional digit to represent the estimated digit (tenths of the smallest calibration).

You might be interested in

20-point physics question! :D

Virty [35]

I think, it must be a chemical. Because the fire is a chemical reaction. So, the chemical energy converted to heat energy.

6 0

3 years ago

Read 2 more answers

Two long, straight wires are separated by 0.120 m. The wires carry currents of 11 A in opposite directions, as the drawing indic

rewona [7]

Answer:

The magnitude of the magnetic field is 1.83 x $10^{-5}$ T.

Explanation:

The flow of an electric current in a straight wire induces magnetic field around the wire. When current is flowing through two wires in the same direction, a force of attraction exists between the wires. But if the current flows in opposite directions, the force of repulsion is felt by the wires.

In the given question, the direction of flow of current through the wires is opposite, thus both wires applies the same field on each other. The result to repulsion between them.

The magnetic field (B) between the given wires can be determined by:

B = $\frac{U_{o}I }{2\pi r}$

where: I is the current, r is the distance between the wires and $U_{0}$ is the magnetic field constant.

But, I = 11 A, r = 0.12 m and $U_{0}$ = 4 $\pi$ x $10^{-7}$ Tm/A

So that;

B = $\frac{4\pi *10^{-7}*11 }{2\pi *0.12}$

= 1.8333 x $10^{-5}$

B = 1.83 x $10^{-5}$ T

6 0

2 years ago

Please help I'm dispirit.

Natasha_Volkova [10]

Synthesis and decomposition reactions are b. Synthesis and decomposition reactions are opposites of each other. Synthesis reactions are in the form A + B → AB, while decomposition reactions are in the form AB → A + B.

Synthesis reactions are reactions in which elements or compounds combine to form a larger compound. They are of the form A + B → AB.

Example: Na(s) + Cl (g)→ NaCl(s)

Decomposition reactions are reactions in which a larger compound breaks up into smaller compounds or elements. They are of the form AB → A + B.

Example: CaCO₃(s) → CaO (s) + CO₂ (g)

Synthesis and decomposition reactions are opposite of each other since synthesis reactions, new substances are formed while in decomposition reactions the compound is broken down into into smaller constituents.

So, Synthesis and decomposition reactions are b. Synthesis and decomposition reactions are opposites of each other. Synthesis reactions are in the form A + B → AB, while decomposition reactions are in the form AB → A + B.

Learn more about reactions here:

brainly.com/question/282113

3 0

2 years ago

A block has two strings attached to it on opposite ends. One string has a force of 5 N,

juin [17]

Unless you have a diagram to include or any other additional info, I'll assume the block is being pulled by two opposing forces along the horizontal surface.

Horizontally, the block is under the influence of

• one rope pulling in one direction with magnitude 15 N,

• the other rope pulling in the opposite direction with mag. 5 N, and

• friction, opposing the direction of the block's motion, with mag. 3 N.

It stands to reason that the block is accelerating in the direction of the larger pulling force.

(A) By Newton's second law, we have

15 N + (-5 N) + (-3 N) = m (1 m/s²)

where m is the mass of the block. Solve for m :

7 N = m (1 m/s²)

m = (7 N) / (1 m/s²)

m = 7 kg

(B) The friction force is proportional to the normal force, so that if f is the mag. of friction and n is the mag. of the normal force, then f = µ n where µ is the coefficient of friction.

The block does not bounce up and down, so its vertical forces are balanced, which means the normal force and the block's weight (mag. w) cancel out:

n + (-w) = 0

n = w

n = m g

where g = 9.8 m/s² is the mag. of the acceleration due to gravity.

n = (7 kg) (9.8 m/s²)

n = 68.6 N

Then

3 N = µ (68.6 N)

µ = (3 N) / (68.6 N)

µ ≈ 0.044

4 0

3 years ago

The bodies of many cars are designed to compress or crumple during an accident. Why are cars built with a crumple zone?

Kryger [21]

By collapsing and crumpling, the force and energy is absorbed by the crumple zone and it is not transferred to the passengers inside. This is a safety feature for the passengers.

8 0

3 years ago