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3 years ago

HELPPPP

Physics

1 answer:

Arisa [49]3 years ago

3 0

Answer:

A. nuclear fusion reactions

C. it's still hot from the big bang

Explanation:

The inside of the earth is hot due to some reasons. This heat provides the internal energy the drives processes within the earth interior. Here are some of the ways in which the heat has accumulated:

Nuclear reactions within the earth interior by fusion and other radioactive processes releases a large amount of heat.
Some heat accreted during the early formation of the earth and has not been lost till this day.
Heating due to friction

These are some of the sources of the earth's internal heat.

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which of these types of radiation do you suppose we should fear the most if administered internally? •gamma rays •neutrons •alph

4vir4ik [10]

Alpha particles, because they are the heaviest ones (helium nuclei) and will travel around the body.

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3 years ago

A cord is used to vertically lower an initially stationary block of mass M = 3.6 kg at a constant downward acceleration of g/7.

dalvyx [7]

Answer:

(a) $W_c=127.008 J$

(b) $W_g=148.176 J$

(c) K.E. = 21.168 J

(d) $v=3.4293m.s^{-1}$

Explanation:

Given:

mass of a block, M = 3.6 kg

initial velocity of the block, $u=0 m.s^{-1}$

constant downward acceleration, $a_d= \frac{g}{7}$

$\Rightarrow$ That a constant upward acceleration of $\frac{6g}{7}$ is applied in the presence of gravity.

∴ $a=- \frac{6g}{7}$

height through which the block falls, d = 4.2 m

(a)

Force by the cord on the block,

$F_c= M\times a$

$F_c=3.6\times (-6)\times\frac{9.8}{7}$

$F_c=-30.24 N$

∴Work by the cord on the block,

$W_c= F_c\times d$

$W_c= -30.24\times 4.2$

We take -ve sign because the direction of force and the displacement are opposite to each other.

$W_c=-127.008 J$

(b)

Force on the block due to gravity:

$F_g= M.g$

∵the gravity is naturally a constant and we cannot change it

$F_g=3.6\times 9.8$

$F_g=35.28 N$

∴Work by the gravity on the block,

$W_g=F_g\times d$

$W_g=35.28\times 4.2$

$W_g=148.176 J$

(c)

Kinetic energy of the block will be equal to the net work done i.e. sum of the two works.

mathematically:

$K.E.= W_g+W_c$

$K.E.=148.176-127.008$

K.E. = 21.168 J

(d)

From the equation of motion:

$v^2=u^2+2a_d\times d$

putting the respective values:

$v=\sqrt{0^2+2\times \frac{9.8}{7}\times 4.2 }$

$v=3.4293m.s^{-1}$ is the speed when the block has fallen 4.2 meters.

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3 years ago

_____ has the potential to superimpose digital data over real photos so that GPS maps can be combined with real pictures of stor

IRISSAK [1]

<u>Augmented reality</u> has the potential to superimpose digital data over real photos so that GPS maps can be combined with real pictures of stores and streets to help people locate their position.

<u>Explanation:</u>

An engaging perception of an original globe atmosphere, where by computer-generated perceptual knowledge the transformation of real-world entities take place and also by multiple sensory modalities, involving somatosensory, visual, auditory, haptic and olfactory forms, thus known as augmented reality.

AR app uses GPS and camera from a smartphone to deploy an augmented reality-enabled GPS navigation system. As in the web, AR tool termed as Real View Navigation is accessible to all Android and iOS clients. Google is brought its first virtual reality walking directions, now recognized as Live Experience on Google Maps.

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3 years ago

A small dog is trained to jump straight up a distance of 1.2 m. How much kinetic energy does the 7.2-kg dog need to jump this hi

LUCKY_DIMON [66]

Answer:84.672 joules.

Explanation:

1) Data:

m = 7.2 kg
h = 1.2 m
g = 9.8 m / s²

2) Physical principle

Using the law of mechanical energy conservation principle, you have that the kinetic energy of the dog, when it jumps, must be equal to the final gravitational potential energy.

3) Calculations:

The gravitational potential energy, PE, is equal to m × g × h

So, PE = m × g × h = 7.2 kg × 9.8 m/s² × 1.2 m = 84.672 joules.

And that is the kinetic energy that the dog needs.

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4 years ago

A giraffe is slowly walking across a field. Is it balanced or unbalanced?

vodka [1.7K]

Your answers are correct

3 0

3 years ago