All categories

4 years ago

Which scientist discovered the two radioactive elements radium anf polonium

Physics

2 answers:

jeka57 [31]4 years ago

8 0

Pierre curie was the one who discovered radium

cricket20 [7]4 years ago

7 0

Answer:

Marie Curie & Pierre Curie

Explanation:

Marie Curie along with her husband Pierre Curie was studying the radioactivity of pitchblende, (also called uranite), the uranium ore

They found that the radioactivity of the pitchblende was radioactive even after removing Uranium and Thorium from it.

In July 1898 they isolated polonium from pitchblende and in December 1898 they isolated radium from pitchblende.

They named polonium after Poland, the homeland of Marie Curie.

You might be interested in

A reaction taking place in a container with a piston-cylinder assembly absorbs 4850. J of heat and has a change in the internal

Maslowich

Answer:

$V_f = 16.3 Ltr$

Explanation:

As per first law of thermodynamics we know that

heat absorbed = change in internal energy + Work done

so we have

$Heat = 4850 J$

$\Delta U = 1618.5 J$

so work done is given as

$4850 = 1618.5 + W$

$W = 3231.5 J$

now we know that at constant pressure the work done is given as

$W = P\Delta V$

$3231.5 = P(V_f - V_i)$

$3231.5 = 5.5 \times 1.01 \times 10^5(V_f - 10.5 \times 10^{-3})$

$V_f = 16.3 \times 10^{-3} m^3$

or we have

$V_f = 16.3 Ltr$

6 0

3 years ago

A 0.5 kg stone is raised from 1m to 2m height from the ground. what is the change in potential energy of the stone?

Usimov [2.4K]

Given: The mass of stone (m) = 0.5 kg

Raised from heights (h₁) = 1.0 m to (h₂) = 2.0 m

Acceleration due to gravity (g) = 9.8 m/s²

To find: The change in potential energy of the stone

Formula: The potential energy (P) = mgh

where, all alphabets are in their usual meanings.

Now, we shall calculate the change in potential energy of the stone

Δ P = P₂ - P₁ = mg (h₂ - h₁)

or, = 0.5 kg ×9.8 m/s² ×(2.0 m - 1.0 m)

or, = 4.9 J

Hence, the required change in the potential energy of the stone will be 4.9 J

4 0

3 years ago

Buoyancy increases with the increase in the density of a) Submerged body b) Fluid

AlekseyPX

Answer:

Submerged body

Explanation:

If buoyancy is greater than weight then object will float.
If buoyancy is less then weight then object will sink.
If buoyancy=weight then objects remains stable

4 0

3 years ago

A toy rocket is launched straight up by using a spring. The rocket is initially pressed down on the spring so that the spring is

Delvig [45]

Answer:

B.6.86 m

Explanation:

Given that

Compression in spring ,x= 9 cm

Spring constant ,K= 830 N/m

Mass of the rocket ,m= 50 g = 0.05 kg ( 1 kg = 1000 g)

Now by applying energy conservation

$\dfrac{1}{2}Kx^2=mgh$

$h=\dfrac{1}{2\times mg}kx^2$

Now by putting the values ( we are taking g= 9.81 m/s²)

$h=\dfrac{1}{2\times 9.81\times 0.05}\times 830\times 0.09^2$

h= 6.853 m

Therefore the answer is B.

B.6.86 m

8 0

3 years ago

Suppose the initial position of an object is zero, the starting velocity is 3 m/s and the final velocity was 10 m/s. The object

Soloha48 [4]

The displacement of an object is obtained by taking out the area of the rectangle plus the area of the triangle under the line.

<h3>What is acceleration?</h3>

Acceleration is defined as the rate change of velocity with time.

acceleration a = (Δv) / (Δt)

Suppose the initial position of an object is zero, the starting velocity is 3 m/s and the final velocity was 10 m/s. The object moves with constant acceleration.

In velocity time graph, the slope determines the acceleration and the area under the curve gives the value for the displacement.

Thus, the displacement of an object is obtained by taking out the area of the rectangle plus the area of the triangle under the line.

Learn more about acceleration.

brainly.com/question/12550364

#SPJ1

8 0

2 years ago