An egg is cracked/broken. Is this egg experiencing a Physical or Chemical change? (Hint: is it still an egg?)

You and your friend throw balloons filled with water from the roof of a several story apartment house. You simply drop a balloon

ivann1987 [24]

Answer:

74.529 m

Explanation:

t = Time taken

u = Initial velocity

v = Final velocity

s = Displacement

a = Acceleration due to gravity = 9.8 m/s²

For first ball

$s=ut+\frac{1}{2}at^2\\\Rightarrow s=0\times t+\frac{1}{2}\times 9.8\times t^2\\\Rightarrow s=4.9t^2\ m$

For second ball

$s=ut+\frac{1}{2}at^2\\\Rightarrow s=50.96\times (t-2.6)+\frac{1}{2}\times 9.8\times (t-2.6)^2\\\Rightarrow s=25.48t-99.372+4.9t^2$

As the displacement is equal

$25.48t-99.372+4.9t^2=4.9t^2\\\Rightarrow t=\frac{99.372}{25.48}\\\Rightarrow t=3.9\ s$

$s=4.9\times 3.9^2=74.529\ m$

So, height of the building is 74.529 m

3 0

3 years ago

How is retrograde motion different from normal diurnal motion

FromTheMoon [43]

Answer:

Diurnal motion, apparent daily motion of the heavens from east to west in which celestial objects seem to rise and set, a phenomenon that results from the Earth's rotation from west to east. The axis of this apparent motion coincides with the Earth's axis of rotation. Retrograde motion is an APPARENT change in the movement of the planet through the sky. It is not REAL in that the planet does not physically start moving backwards in its orbit. It just appears to do so because of the relative positions of the planet and Earth and how they are moving around the Sun.

6 0

3 years ago

Suppose your grocery cart is moving at a constant momentum in a straight line down the aisle of a store, without friction. How w

Strike441 [17]

Answer:

It will increase

Explanation:

The kinetic energy is the energy possessed by a moving object and is given by:

KE = $1/2 mv^2$

where m = mass of the object and v = velocity of the object.

It does means that the more the mass of an object in motion, the more the kinetic energy of the object if there are no opposing force such as friction. Also, the more the kinetic energy of the object, the more the speed of that object.

<em>Hence, as the weight of the cart increases by addition of groceries, the kinetic energy increases and the speed also increases as it moves along the frictionless surface.</em>

7 0

3 years ago

A crude but useful approximation for an incompressible boundary layer is a cubic variation from u = 0 at the surface (y = δ) to

Vinvika [58]

Answer:

Explanation:

The detailed steps and appropriate differentiation and integration is as shown in the attachment.

Starting from the equation for the profile is u/U = 3/2(y/δ) – 1/2(y/δ)3

7 0

3 years ago

Two masses are joined by a massless string. A 30-N force applied vertically to the upper mass gives the system a constant [Ans :

Vilka [71]

Answer:

12/13 kg, 18/13 kg

Explanation:

Let the masses are m and m'.

acceleration, a = 3.2 m/s^2

Force, F = 30 N

Tension, T = 18 N

By the diagram, using Newton's second law

F - T - m'g = m' a .... (1)

T - mg = ma ..... (2)

Substitute the values of F, T and a in equation (1) and equation (2)

30 - 18 = m' (9.8 + 3.2)

12 = 13 m'

m' = 12/ 13 kg

And, 18 = m (9.8 + 3.2)

m = 18/13 kg

8 0

3 years ago