Which of the following statements is true?

igomit [66]

Explanation:

measurement of a set, accuracy is closeness of the measurements to a specific value, while precision is the closeness of the measurements to each other.

Accuracy has two definitions:

More commonly, it is a description of systematic errors, a measure of statistical bias; low accuracy causes a difference between a result and a "true" value. ISO calls this trueness.

Alternatively, ISO defines[1] accuracy as describing a combination of both types of observational error above (random and systematic), so high accuracy requires both high precision and high trueness.

Precision is a description of random errors, a measure of statistical variability.

In simpler terms, given a set of data points from repeated measurements of the same quantity, the set can be said to be accurate if their average is close to the true value of the quantity being measured, while the set can be said to be precise if the values are close to each other. In the first, more common definition of "accuracy" above, the two concepts are independent of each other, so a particular set of data can be said to be either accurate, or precise, or both, or neither.

3 0

3 years ago

A particle of mass m = 13 kg moves in space under the action of a conservative force. Its potential energy is given by PE = 2xyz

Helen [10]

Answer:

$F_{x}$ = -12 N , $F_{y}$ = -80 N and $F_{z}$ = - 44 N

Explanation:

The force is related to the potential energy by the formula

F = -Δ U = - ( $\frac{dU}{dx}$ i ^ + $\frac{dU}{dy}$ j ^ + $\frac{dU}{dz}$ k ^)

It indicates the potential energy

U = 2xyz + 3z² + 4yx + 16

To solve this problem let's make the derivatives, to find each component of the force

$\frac{dU}{dx}$ = 2yz + 0 + 4y + 0 = 2yz + 4y

$\frac{dU}{dx}$ = 2xz + 0 + 4x + 0 = 2xz + 4x

$\frac{dU}{dx}$ = 2xy + 3 2z + 0 +0 = 2xy + 6z

We look for the expression for the force in each axis

$F_{x}$ = - 2yz - 4y

$F_{y}$ = -2xz -4x

$F_{z}$ = -2xy -6z

We calculate at the point P = (20 i ^ + 1j ^ + 4 k ^) m

$F_{x}$ = - 2 1 4 - 4 1

$F_{x}$ = -12 N

$F_{y}$ = - 2 20 4 - 4 20

$F_{y}$ = -80 N

$F_{z}$ = - 20 1 - 6 4

$F_{z}$ = - 44 N

We put together the expression for strength

F = (-12 i ^ - 80j ^ -44k ^) N

5 0

4 years ago

Which of these statements best describes the difference between electromagnetic and gravitational forces in the solar system?

kodGreya [7K]

It's B-<span>Electromagnetic forces are stronger than gravitational forces</span>

5 0

3 years ago

Read 2 more answers

What pattern does the earth revolve around the sun?.

Whitepunk [10]

Answer: The Earth moves around the Sun in an extended circular or oval pattern. Or otherwise known as an "elliptical" orbit.

Hope this helps!

7 0

2 years ago

Read 2 more answers

6. A 1,780kg car moving at 14m/s takes a turn around a circle with a radius of 50.0m.

m_a_m_a [10]

1) Centripetal acceleration: $3.9 m/s^2$

2) Centripetal force: 6942 N

Explanation:

1)

For an object moving in uniform circular motion (=circular motion with constant speed), the net acceleration is the centripetal acceleration, directed towards the centre of the trajectory and whose magnitude is given by

$a=\frac{v^2}{r}$