What do deltas and natural levees have in common?

Picture showing four cards in a row with labels 'First animal appears on land', 'First life form appears in the sea', 'First roc

sasho [114]

The answer would be 'First rocks formed on Earth'.

3 0

3 years ago

Suppose you have made the following hypothesis:

Blizzard [7]

Answer:

Explanation:

You could look up the shark population near specific coral reefs. You could also go the simple route and say something like, "sharks eat fish so, sharks will go where the fish are and if there are fish in the coral reefs, (which there are) they would be most likely to go there". I know this may not be the answer you were looking for but its the best I've got.

3 0

3 years ago

Read 2 more answers

Two identical masses, A and B, slide down frictionless ramps, both starting at a height of 3M above the ground. Object A slides

balu736 [363]

Answer: c. Neither, they have the same speed.

In both the cases, there will be work done by the gravitational force. Since, the gravitational force is a conservative force, its work done does not depend on the path as it only depends on the initial and final position of the objects. Since, the initial and final positions are same for both the objects, the work done by gravitational force will be same in both the cases.

Hence, Work done by gravitational force = Change in the kinetic energy

So, the kinetic energy will be same for both the object.

Since, the masses are same: Kinetic energy = $\frac{1}{2}mv^2$

Hence, the speed will also be same for both the objects.

Correct option: C

3 0

3 years ago

g A 1.5 kg block is initially at rest on a horizontal frictionless surface when a horizontal force along an x axis is applied to

lidiya [134]

Answer:

(a). The kinetic energy is 5.33 J

(b). The maximum kinetic energy is 5.33 J.

Explanation:

Given that,

Mass of block = 1.5 kg

Suppose the force is

$F=(4-x^2)i\ N$

(a). We need to calculate the kinetic energy of the block

Using work energy theorem

$\Delta k=W_{f}$

$K(x)=\int_{0}^{x}{4-x^2}dx$

$K(x)=4x-\dfrac{x^3}{3}$ ....(I)

Now put the value of x in equation

$K(x)=4\times2-\dfrac{2^3}{3}$

$K(x)=5.33\ J$

The kinetic energy is 5.33 J

For K to be minimum

$\dfrac{dK}{dx}=0$

$4-\dfrac{3x^2}{3}=0$

$4-x^2=0$

$x=2$

(b). We need to calculate the maximum kinetic energy of the block

For K to be maximum

$\dfrac{d^2K}{dx^2}=0$

$\dfrac{d^2K}{dx^2}=0-2x$

Put the value of x

$\dfrac{d^2K}{dx^2}=-4$

Now put the value of x in equation (I)

$K(x)=4\times2-\dfrac{2^3}{3}$

$K(x)=5.33\ J$

The maximum kinetic energy is 5.33 J

Hence, (a). The kinetic energy is 5.33 J

(b). The maximum kinetic energy is 5.33 J.

3 0

3 years ago

Using your hand to exert a horizontal force, you push a physics textbook across the floor at a steady pace. the frictional force

ahrayia [7]

Since the book moves at a constant speed its acceleration is zero. Using Newton's 2nd law F=ma, where a is zero in constant velocity, requires that F=0. Since the forces are in different directions and sum to zero, the forces are equal and opposite. So the push is exactly equal to the friction force.

3 0

3 years ago