How is the mass of air in a hot air balloon affected when it is floating?

A student tosses a ball horizontally from a balcony to a friend 3.8 meters down below them. How long does the ball take to reach

Vsevolod [243]

Answer:

The time it takes the ball to fall 3.8 meters to friend below is approximately 0.88 seconds

Explanation:

The height from which the student tosses the ball to a friend, h = 3.8 meters above the friend

The direction in which the student tosses the ball = The horizontal direction

Given that the ball is tossed in the horizontal direction, and not the vertical direction, the initial vertical component of the velocity of the ball = 0

The equation of the vertical motion of the ball can therefore, be represented by the free fall equation as follows;

h = 1/2 × g × t²

Where;

g = The acceleration due gravity of the ball = 9.81 m/s²

t = The time of motion to cover height, h

Then height is already given as h = 3.8 m

Substituting gives;

3.8 = 1/2 × 9.81 × t²

t² = 3.8/(1/2 × 9.81) ≈ 0.775 s²

∴ t = √0.775 ≈ 0.88 seconds

The time it takes the ball to fall 3.8 meters to friend below is t ≈ 0.88 seconds.

8 0

3 years ago

The reaction is at dynamic equilibrium.

DiKsa [7]

Answer:

Nitrogen and hydrogen combine at the same rate that ammonia breaks down.

Explanation:

7 0

3 years ago

Can someone help me?!!!!!

ladessa [460]

Answer:

magnitude: 21.6; direction: 33.7 degrees

Explanation:

When we multiply a vector by a scalar, we have to multiply each component of the vector by the scalar number. In this case, we have

vector: (-3,-2)

Scalar: -6

so the vector multiplied by the scalar will have components

$(-3\cdot (-6), -2 \cdot (-6))=(18,12)$

The magnitude is given by Pythagorean's theorem:

$m=\sqrt{18^2+12^2}=21.6$

and the direction is given by the arctan of the ratio between the y-component and the x-component:

$\theta = tan^{-1} (\frac{12}{18})=33.7^{\circ}$

3 0

3 years ago

The International Space Station (ISS) orbits Earth at an altitude of 4.08 × 105 m above the surface of the planet. At what veloc

alukav5142 [94]

This question involves the concepts of orbital velocity and orbital radius.

The orbital velocity of ISS must be "7660.25 m/s".

The orbital velocity of the ISS can be given by the following formula:

$v=\sqrt{\frac{GM}{R}}$

where,

v = orbital velocity = ?

G = Universal Gravitational Constant = 6.67 x 10⁻¹¹ N.m²/kg²

M = Mass of Earth = 5.97 x 10²⁴ kg

R = orbital radius = radius of earth + altitude = 63.78 x 10⁵ m + 4.08 x 10⁵ m

R = 67.86 x 10⁵ m

Therefore,

$v=\sqrt{\frac{(6.67\ x\ 10^{-11}\ N.m^2/kg^2)(5.97\ x\ 10^{24}\ kg)}{67.86\ x\ 10^5\ m}}$

Learn more about orbital velocity here:

brainly.com/question/541239

3 0

2 years ago

A circle graph shows that one-fourth of the students in a particular school ride the bus every day. What is this equivalent meas

Aleonysh [2.5K]

Answer:

it's 1.57... radians and 90°

3 0

3 years ago