If you travel 450 meters in 40 seconds, what is your average speed in meters per

Please help (choose a b or c)

Dafna11 [192]

I GEUSS A and COM is correct answer to this question

3 0

3 years ago

Read 2 more answers

Why do plane mirrors and convex mirrors form only virtual images?

Alekssandra [29.7K]

<span>B. because they cannot make light rays converge</span>

7 0

3 years ago

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ryan hypothesizes that darker colors heat up faster. he places a thermometer inside a red wool sock, a green cotton glove, and a

telo118 [61]

Light are transfer through waves in the atmosphere and yes it true that the darker the color is the more heat it could absorb thus it is also explain that the lighter the color is the less heat or light its absorb its because the light is bounces back through other form of light and it lessens the amount of heat in a substance. In Ryan's procedure the possible wrong that he done is the present of a green cotton glove. Green color are one of the color that bounces light and could not support the hypothesis of Ryan and the possible temperature he could get is not the accurate one.

3 0

3 years ago

Let the four horizontal compass directions north, east, south, and west be represented by units vectors n^, e^, s^, and w^, resp

Marrrta [24]

Answer:

c = e > b = d > a

Explanation:

Given vectors are all unit vectors, therefore they have a magnitude of 1

<h3>Let a, b be two vectors and magnitude of cross product of these two vectors is (magnitude of a) × (magnitude of b) × (sine of angle between these two vectors)</h3>

As all are unit vectors their magnitude is 1 and therefore in this case the cross product between any two vectors depends on the sine of angle between those two vectors

In option a as both the vectors are same, the angle between them will be zero and sin0° will also be 0

In option b angle between those two vectors is 135° and sin135° is 1 ÷ √2

In option c angle between those two vectors is 90° and sin90° is 1

In option d angle between those two vectors is 45° and sin45° is 1 ÷ √2

In option e angle between those two vectors is 90° and sin90° is 1

So by comparison of magnitudes of cross products in each option, the order will be c = e > b = d > a

5 0

3 years ago

After polishing his 2-kg wrestling trophy, Mike sets it down on the ground and walks away to find more polish. Meanwhile, Julie

klio [65]

1) The initial momentum of the trophy is zero

2) The initial momentum of the bowling ball is 160 kg m/s

3) The total momentum before the collision is 160 kg m/s

4) The total momentum of the system after the collision is 160 kg m/s

5) The final velocity of the trophy is 32 m/s

Explanation:

1)

The momentum of an object is given by

$p=mv$

where

m is the mass of the object

v is its velocity

In this problem, the data for the trophy before the collision are:

m = 2 kg is the mass

v = 0 is its initial velocity

Therefore, the initial momentum of the trophy is

$p_1=(2)(0)=0$

2)

Using the same equation used in part 1), the initial momentum of the bowling ball is

$p=mv$

where

m is the mass of the bowling ball

v is its initial velocity

The data of the problem are

m = 8 kg is the mass

v = 20 m/s is the velocity

Substituting,

$p_2=(8)(20)=160 kg m/s$

3)

The total momentum of the system before the collision is given by the sum between the initial momentum of the trophy and the initial momentum of the bowling ball:

$p_i = p_1 + p_2$

where

$p_1$ is the initial momentum of the trophy

$p_2$ is the initial momentum of the ball

Here we have

$p_1 = 0$

$p_2 = 160 kg m/s$

Therefore, the total momentum is

$p_i = 0 + 160 = 160 kg m/s$

4)

According to the law of conservation of momentum, for an isolated system (=no external unbalanced forces acting on the system), the total momentum of the system is conserved before and after the collision:

$p_i = p_f$

where

$p_i$ is the total momentum before the collision

$p_f$ is the total momentum after the collision

If we consider the system in the problem to be isolated (i.e. no frictional forces acting on the ball or the trophy), we can therefore say that the total momentum after the collision must be equal to the total momentum before the collision: therefore,

$p_f = 160 kg m/s$