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2 years ago

What do fossils provide evidence for?

Physics

2 answers:

Alenkasestr [34]2 years ago

8 0

B

Fossils show us what species lived in an area before humans were there.

Lapatulllka [165]2 years ago

7 0

Answer: B. the history of life in the geologic past

Explanation:

B. the history of life in the geologic past because fossils help us by telling what type of animals were alive back then ex ) a dinosaur fossil shows us what type of dinosaur it was

PLEASE MARK BRANILIEST

You might be interested in

2. A can filled with sand has a mass of 0.65kg is swung overhead in a horizontal circle of radius 0.70m at a constant rate of 2.

Aliun [14]

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

≈ 5 Kgm²/sec

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

Angular momentum is given by the formula

L = Iω, where I is the moment of inertia and ω is the angular speed.

I = mr², where m is the mass and r is the radius

= 0.65 × 0.7²

= 0.3185

Angular speed, ω = v/r

= (2 × 3.142 × r × 2.5) r

= 15.71

Therefore;

Angular momentum = Iω

= 0.3185 × 15.71

= 5.003635

<u>≈ 5 Kgm²/sec</u>

6 0

3 years ago

An object at rest on a flat, horizontal surface explodes into two fragments, one seven times as massive as the other. The heavie

Veronika [31]

Answer:

Explanation:

Given that,

One fragment is 7 times heavier than the other

Let one fragment mass be M

Let this has a velocity v

And the other 7M

And this a velocity V

Initially the fragment is at rest u = 0

Applying conservation of momentum

Momentum is given as p=mv

Initial momentum = final momentum

Po = Pf

(M+7M) × 0 = 7M •V − Mv

0 = 7M•V - Mv

Divide both sides by M

0 = 7V -v

v = 7V

Since friction decelerates the masses to zero speed, we can calculate the NET work on the individual blocks and relate this quantity to the change in kinetic energy of each block

The workdone by the 7M mass is

Distance moved by 7M mass is 6.8m, Then, d =6.8m

W = fr × d

Where fr = µkN

When N=W =mg, where m=7M

N= 7Mg

fr = −µk × 7mg

Then, W(7m) = −7µk•Mg×d

W(7m) = −7µk•Mg×6.8

W(7m) = −47.6 µk•Mg

Then, same procedure,

Let distance move by the small mass be m

Work done by M mass

W(m) = −µk•Mg×d'

Since it is a wordone by friction, that is why we have a negative sign.

Using conservation of energy

Work done by 7M mass is equal to work done by M mass

W(7m) = W(m)

−47.6 µk•Mg = −µk•Mg×d

Then, M, g and µk cancels out

We are left with

-46.7 = -d

Then, d = 46.7m

7 0

3 years ago

Read 2 more answers

When a 25-kg crate is pushed across a frictionless horizontal floor with a force of 200 N, directed 20 below the horizontal, th

Fofino [41]

Answer:

Option E is correct 310N

Explanation:

Given that the force used to push the crate is F = 200N

The force directed 20° below the horizontal

Mass of crate is m = 25kg

Weight of the crate can be determine using

W = mg

g is gravitational constant =9.8m/s²

W = 25×9.8

W = 245 N

Check attachment. For free body diagram and better understanding

Using newton second law along the vertical axis since we want to find the normal force

ΣFy = m•ay

ay = 0, since the body is not moving in the vertical or y direction

N—W—F•Sin20 = 0

N = W+F•Sin20

N = 245+ 200Sin20

N = 245 + 68.4

N = 313.4 N

The normal force is approximately 310 N to the nearest ten

3 0

3 years ago

What is displacement

saveliy_v [14]

This is what wiki says hope it helps
A displacement is a vector whose length is the shortest distance from the initial to the final position of a point P.[1] It quantifies both the distance and direction of an imaginary motion along a straight line from the initial position to the final position of the point.

A displacement may be also described as a 'relative position': the final position of a point (Sf) relative to its initial position (Si), and a displacement vector can be mathematically defined as the difference between the final and initial position vectors:

4 0

3 years ago

Read 2 more answers

If a 10.0 kg object is on a surface that is inclined 30o and the coefficient of static friction is 0.65, what is the force of st

Alexxandr [17]

fraction equation is<span>
F =µR
F=friction,µ=coefficient , R=reaction = mg

use same equation for b part, but the reaction is no longer mg because the plain is now inclined. Draw a forces diagram and you will see that the reaction force can be calculated from the weight of the object and inclination of the plain using trigonometry.</span>

6 0

3 years ago