A block is sitting on a platform 20 m high. It weighs 50 kg. How much potential energy does it contain?

A 52 kg and a 95 kg skydiver jump from an airplane at an altitude of 4750 m, both falling in the pike position. Assume all value

Scilla [17]

Answer: 52 kg skydiver: 9.09 m/s and 522.55 s

95 kg skydiver: 12.3 m/s and 386.2 s

Explanation: Drag Force is an opposite force when an object is moving in a fluid.

For skydivers, when falling through the air, the forces acting on it are gravitational and drag forces. At a certain point, drag force equals gravitational force, which is constant on any part of the planet, producing a net force that is zero. Since there is no net force, there is no acceleration and, consequently, velocity is constant. When that happens, the person reached the Terminal Velocity.

Drag Force and Velocity are proportional to the squared speed. So, terminal velocity is given by:

$F_{G}=F_{D}$

$mg=\frac{1}{2}C \rho Av_{T}^{2}$

$v_{T}=\sqrt{\frac{2mg}{\rho CA} }$

where

m is mass in kg

g is acceleration due to gravitational force in m/s²

ρ is density of the fluid in kg/m³

C is drag coefficient

A is area of the object in the fluid in m²

Calculating:

The 52kg skydiver has terminal velocity of:

$v_{T}=\sqrt{\frac{2(52)(9.8)}{(1.21)(0.7)(0.14)} }$

$v_{T}=$ 9.09

The 95kg skydiver's terminal velocity is

$v_{T}=\sqrt{\frac{2(95)(9.8)}{(1.21)(0.7)(0.14)} }$

$v_{T}=$ 12.3

The 52 kg and 95kg skydivers' terminal velocity are 9.09m/s and 12.3m/s, respectively.

The time each one will reach the floor will be:

52 kg at 9.09 m/s:

$t=\frac{4750}{9.09}$

t = 522.5

95 kg at 12.3 m/s:

$t=\frac{4750}{12.3}$

t = 386.2

The 52 kg and 95kg skydivers' time to reach the floor are 522.5 s and 386.2 s, respectively.

3 0

2 years ago

How can light energy solve our real life problem?

kifflom [539]

Answer:

It gives our light which we need for probably everything.

Explanation:

4 0

3 years ago

Read 2 more answers

Plzzz help will mark the brainliest

ANEK [815]

Ciara is winging....etc
The answer is : 0.60 N, toward the center of the circle

A satellite....etc
The Answer is : 7400 m/s

What is the .....etc
The Answer is : 2.60 m/s

8 0

3 years ago

Three basic electrical effects occur when an electric current flows in a conductor: A magnetic field is set up around the conduc

Alex787 [66]

Answer:

A drop in voltage occurs

Explanation:

When electric current flows through a conduct, there are three basic electrical effects that occur to the conductor;

1. A magnetic field is set up around the conductor,

A magnetic field is formed around a conductor when current flows through it which makes it acts like a magnet. Application is used in electric bells.

2. Heat is generated, and

The heating effect of current is due to the conversion of some of the electrical energy that passes through the conductor, into heat energy. Application of heat effect include electric iron, microwave oven, electric bulb, hair straightener etc.

H = I²Rt

3. A drop in voltage occurs

Voltage drop is as a result of current passing through the impedance offers by the conductor or circuit elements. When current passes through a conductor, the resistance offers opposition to the flow of the electric current according to Ohm's law.

7 0

3 years ago

A bat moving at 3.7 m/s is chasing a ying insect. The bat emits a 36 kHz chirp and receives back an echo at 36.79 kHz. At what s

3241004551 [841]

Answer:

The speed the bat is gaining on its prey is 0.03m/s

Explanation:

Given;

speed of the bat, v₀ = 3.7 m/s

frequency of the bat, F₀ = 36 kHz

frequency of the source, Fs = 36.79

This is relative motion between a source of the sound and the observer. The phenomenon is known as Doppler effect.

Apply the following equation to determine the speed of the insect which is the source;

$F_0 = F_s[\frac{v+v_0}{v-v_s} ]\\\\\frac{F_0}{F_s} = [\frac{v+v_0}{v-v_s} ]\\\\\frac{36.79}{36} = \frac{340+3.7}{340-v_s}\\\\1.0219 = \frac{343.7}{340-v_s}\\\\ 340-v_s = \frac{343.7}{1.0219}\\\\340-v_s = 336.33\\\\v_s = 340-336.33\\\\v_s = 3.67 \ m/s$

The speed the bat is gaining on its prey = 3.7m/s - 3.67m/s = 0.03 m/s

Therefore, the speed the bat is gaining on its prey is 0.03m/s

8 0

2 years ago