All categories

4 years ago

Att=0 a car has a speed of 30 m/s. Att-6 s, its speed is 14 m/s.

Physics

1 answer:

miss Akunina [59]4 years ago

3 0

The average acceleration during this time interval is $-2.67 \mathrm{m} / \mathrm{s}^{2}$

Explanation:

Average acceleration can be measured as the ratio of change in speed to change in time. As the initial speed at initial time is 30 m/s at t = 0 and then at t = 6 s, the speed is decreased to 14 m/s. Then the average acceleration will be

$Average acceleration =\frac{14-30}{6-0} =-2.67m/s^{2}$

So the average acceleration is negative which indicates that there is deceleration occurrence in the system.

You might be interested in

What is the difference between muscular endurance and muscular strength? A B or C

Galina-37 [17]

Answer:

Muscular endurance is how many times you can move a weight without getting tired.

Muscular strength is the amount force you can put out.

7 0

3 years ago

What is the element with the lowest electronegativity value?

Lerok [7]

<h2>Answer: Francium </h2>

Let's start by explaining that electronegativity is a term coined by Linus Pauling and is determined by the ability of an atom of a certain element to attract electrons when chemically combined with another atom.

So, the more electronegative an element is, the more electrons it will attract.

It should be noted that this value can not be measured directly by experiments, but it can be determined indirectly by means of calculations from other atomic or molecular properties of the element. That is why the scale created by Pauling is an arbitrary scale, where the maximum value of electronegativity is 4, assigned to Fluorine (F) and the lowest is 0.7, assigned to Francium (Fr).

7 0

4 years ago

The length of a simple pendulum is 0.81 mand the mass of the particle (the "bob") at the end of the cable is0.23 kg. The pendulu

Gemiola [76]

Answer:

$\displaystyle w=3.478\ rad/sec$

$M=0.0182\ J$

$v=0.398\ m/s$

Explanation:

Simple Pendulum

It's a simple device constructed with a mass (bob) tied to the end of an inextensible rope of length L and let swing back and forth at small angles. The movement is referred to as Simple Harmonic Motion (SHM).

(a) The angular frequency of the motion is computed as

$\displaystyle w=\sqrt{\frac{g}{L}}$

We have the length of the pendulum is L=0.81 meters, then we have

$\displaystyle w=\sqrt{\frac{9.8}{0.81}}$

$\displaystyle w=3.478\ rad/sec$

(b) The total mechanical energy is computed as the sum of the kinetic energy K and the potential energy U. At its highest point, the kinetic energy is zero, so the mechanical energy is pure potential energy, which is computed as

$U=mgh$

where h is measured to the reference level (the lowest point). Please check the figure below, to see the desired height is denoted as Y. We know that

$H+Y=L$

And

$H=L\ cos\alpha$

Solving for Y

$Y=L(1-cos\alpha )$

$Since\ \alpha=8.1^o, L=0.81\ m$

$Y=0.0081\ m$

The potential energy is

$U=mgh=0.23\ kg(9.8\ m/s^2)(0.0081\ m)$

$U=0.0182\ J$

The mechanical energy is, then

$M=K+U=0+U=U$

$M=0.0182\ J$

(c) The maximum speed is achieved when it passes through the lowest point (the reference for h=0), so the mechanical energy becomes all kinetic energy (K). We know

$\displaystyle K=\frac{mv^2}{2}$

Equating to the mechanical energy of the system (M)

$\displaystyle \frac{mv^2}{2}=0.0182$

Solving for v

$\displaystyle v=\sqrt{\frac{(2)(0.0182)}{0.23}}$

$v=0.398\ m/s$

4 0

3 years ago

1. Current is usually the flow of

kolbaska11 [484]

Answer:

1. Current is usually the flow of electrons.

Explanation:

The flow of charges through a wire or conductor is called electric current.

7 0

3 years ago

Read 2 more answers

You are operating a powerboat at night. Your red sidelight must be visible to boats approaching from which direction(s)

Dmitriy789 [7]

The answer is the red sidelight on a powerboat should be visible from the front and from the left (port side).

What are Sidelights?

There is various combinations of lights that must be used on a boat when it is dark, and these are:
Sidelights: These lights are called combination lights and are red and green. The red sidelight must be visible from the port side and the green light indicates the right side (the starboard).
Stern light: The stern light is seen at the back end of the vessel.
Masthead Light: The masthead light is a white light that shines forwards and on all sides of the vessel. All powered vessels must use this light.
All-Round white light: This light is the major light that is used to join the masthead light and the stern light. This single light is visible to all vessels from all directions.
Thus, as a rule for a boat rider, he should show the vision of red light and it should be visible from the front and from the left (port side).

To learn more about Sidelights visit:

brainly.com/question/28205057

#SPJ4

4 0

2 years ago