Ask question

Ask question

All categories

3 years ago

13

The position-time graph for a bug crawling along a line is shown in item 4 below. Determine whether the velocity is positive, ne

gative, or zero at each of the times marked on the graph.

1 answer:

Naddika [18.5K]3 years ago

5 0

Answer: The velocity at different marked time points are given as

t1 = -

t2 = +

t3 = +

t4 = -

t5 = 0

Explanation:

The slope of the tangent of the curve indicates the instantaneous velocity. So if the slope of the tangent is positive, that Is, the tangent makes a positive angle (above the horizontal axis) with the horizontal

axis, then the velocity at this point is positive, and if the slope of the tangent is negative, that is the tangent makes a negative angle with the horizontal axis (below the horizontal axis), then the velocity at this point is negative.

When the tangent of the line is parallel to the horizontal axis, the velocity is 0.

From the position-time graph attached, the sign on the instantaneous velocity for each time marked on the graph is given below

t1 = -

t2 = +

t3 = +

t4 = -

t5 = 0

QED!

You might be interested in

Explain why ionizing radiation is dangerous?

Dafna11 [192]

Answer:

When the dose is high enough, ionizing radiation causes two types of harm to humans: direct tissue damage and cancer. Direct tissue damage happens when enough molecules are broken apart that the cells simply can no longer function. This can lead to radiation burns, radiation sickness, organ failure, and even death.

8 0

3 years ago

The vibrations produced by a jackhammer are used to break up pavement. What type of waves did/does the jackhammer produce into t

klio [65]

<span>P waves

P-waves are sometimes called pressure waves, and sometimes they are called longitudinal waves. P-waves are transmitted through the Earth’s interior with a backwards and forwards motion along the line of travel, by alternating compression and dilatation. A jack hammer creates P-waves. They are capable of passing through any type of material they encounter, including the liquid of the Earth’s outer core, although they
will be bent and deflected when they pass across the boundaries separating
layers of different densities.

I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
</span>

8 0

4 years ago

You are standing in front of a flat large mirror. As you step 1.0 m farther from the mirror, the distance between you and your i

Lesechka [4]

Answer:

2 meters

Explanation:

when you step away from a reflection you get farther

5 0

3 years ago

Two objects, T and B, have identical size and shape and have uniform density. They are carefully placed in a container filled wi

Korvikt [17]

Complete Question:

Two objects, T and B, have identical size and shape and have uniform density. They are carefully placed in a container filled with a liquid. Both objects float in equilibrium. Less of object T is submerged than of object B, which floats, fully submerged, closer to the bottom of the container. Which of the following statements is true?

Object T has a greater density than object B.
Object B has a greater density than object T.
Both objects have the same density.

Answer:

Object B has a greater density than object T

Explanation:

Any object partially or completely submerged in a liquid, experiments an upward force, equal to the weight of the volume displaced by the liquid. This force is called the buoyant force, and can be expressed as follows:

Fb = ρl * Vs*g

where ρl is the density of the liquid, and Vs is the submerged volume.

This force must be compared with the weight of the object, which is always downward, and can be expressed as follows:

Fg = ρb* Vb * g

where ρb, is the density of the object, and Vb is the total volume of the object, regardless which portion is submerged.

For object B, as it floats fully submerged, this means that both forces are equal in magnitude:

Fg = Fb⇒ ρb* Vb * g = ρl * Vs*g

As Vb = Vs (the object is fully submerged) this means that ρb =ρl.

For object T, as it floats partially submerged, this means that Fg < Fb:

Fg= ρt* Vt * g < Fb = ρl * Vs*g.

Now, we know that ρb =ρl, so we can replace in the equation above:

ρT* Vt * g < ρb*Vs*g

Simplifying common terms, and replacing Vs by KVt (where K is the fraction of the total volume which is submerged, i.e. K<1), we have:

ρt*Vt < ρb*K*Vt ⇒ ρt / ρb < K < 1 ⇒ ρt < ρb ⇒ ρb > ρt

3 0

3 years ago

An 800 N box is pushed across a level floor for a distance of 5.0 m with a force of 400 N. How much work was done on this box.

AveGali [126]

Answer: 2000 J.

Explanation: Since work is force*displacement, we just have to multiply the force by the distance: w = f*d = 400 N*5.0 m = 2000 J.

4 0

3 years ago