Which of the following is known as the following cycle because it's reservoir is a rock.

Why is it that we can see blood cells only with a microscope? A) The cells form clumps. B) The cells keep moving about. C) The c

Snezhnost [94]

D the cells are very small

7 0

3 years ago

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In a ballistics test, a 24 g bullet traveling horizontally at 1300 m/s goes through a 25-cm-thick 360 kg stationary target and e

MaRussiya [10]

Answer:

A)0.00022s b)40363.6N c) 0.025m/s

Explanation:

Mass = 24g = 0.024kg, distance though the target = thickness of the target = 25cm = 0.25m

Initial speed of the bullet = 1300m/s, final speed = 930m/s

Using equation of motion

Distance = 1/2(vf+vi)*t (time in seconds)

t = 0.25*2/(1300+930) = 0.00022s

B) force exerted on the body

F = ma = m* (vf-vi)/t = 0.024*(930-1300)/0.00022

F = -40363N, it is negative because the body decelerated during this motion

C) using law of conservation of momentum,

M1*U1+ M2*U2(M2and U1 are the mass and initial speed of the body) = M1V1+ M2V2

The target was at rest so initial speed U2 = 0

0.024*1300 + 360*0 = 0.024*930 + 360*V2

31.2 = 22.32+360*V2

31.2-22.33 = 360*V2

V2 = 8.88/360 = 0.025m/s

8 0

3 years ago

Please someone help me.

katovenus [111]

Answer:

acceleration of the car is 3 m\s^2

Explanation:

from rest means the initial velocity (vi) is zero

time = 5s

final velocity (vf) = 15m\s

a = vf - vi \ t

a = (15-0) \ 5

a= 3 m\s^2

which means that the car is speeding up 3 meters every second

5 0

4 years ago

Derive an expression for the total mechanical energy of the system as the monkey reaches the top of the motion, Etop, in terms o

ipn [44]

Answer:

U = 0.5 * k *(x + d - h_max)^2 + m*g*h_max

Explanation:

Given:

- The extension in spring @ equilibrium = x m

- The spring constant = k

- The amount of distance pulled down = d

- mass of the toy = m

Find:

- The total mechanical energy E_top at the top position h_max in terms of the available variables.

Solution:

- First we need to determine the types of Energy that are in play:

- The Elastic potential Energy E_p in a spring is given:

E_p: 0.5 * k * (ext)

- In our case when the toy at the top most position h_max will have a net extension ext, by summing displacement of spring:

ext = Equilibrium + distance pulled - h_max = (x + d - h_max)

Hence, the elastic potential energy will be:

E_p = 0.5 * k *(x + d - h_max)^2

- The gravitational potential energy E_g is given by:

E_g = m*g*h_max

Where, bottom most position is taken as reference (datum).

- The kinetic Energy E_k is given by:

E_k = 0.5*m*v_top^2

- Since we know that the maximum height is reached when velocity is zero

Hence, E_k = 0.5*m*0^2 = 0.

The total Energy of the system U is sum of all energies and play:

U = E_p + E_k + E_g

U = 0.5 * k *(x + d - h_max)^2 + m*g*h_max

8 0

4 years ago

Which elastic modulus describes the relationship between stress and strain for a block of iron sliding across a horizontal floor

Juliette [100K]

Answer:

B. Shear Modulus

Explanation:

In this scenario, the friction force between the sliding block and the floor causes the block to deform.

Hence, the elastic modulus which describes the relationship between stress and strain for a block of iron sliding across a horizontal floor is Shear Modulus.

Shear Modulus can be defined as the ratio of shear stress to shear strain with respect to a physical object.

This ultimately implies that, Shear Modulus arises as a result of the application of a shear force on an object or body which eventually leads to its deformation. Thus, this phenomenon is simply used by scientists to measure or determine the rigidity of an object or body.

Mathematically, Shear Modulus is given by the formula;

$G = \frac {Fl}{ADx}$

Where;

G is the Shear Modulus.

F is the force applied to the object.

A is the area of the object.

l is the length of the object.

Dx is the change in length.

Shear Modulus is measured in Pascals.

3 0

3 years ago