That particular group of elements is reffered to as the "Noble Gasses"--a title that comes from the fact that these gases are very "secure" and don't mix well with other elements.

4 0

3 years ago

When u write on a piece of glass sheet with a piece of chalk , the writing is not clear explain .

svetlana [45]

Becuse your weighting with chalk that has pigment

6 0

3 years ago

block with of mass m is at rest on horizontal frictionless surface at time t=0. A force given by F=Bt+C is applied horizontally

Alexeev081 [22]

Answer:

$v_{2} =\frac{1}{2}$

Explanation:

From the second law of Newton movement laws, we have:

$F=m*a$ , and we know that a is the acceleration, which definition is:

$a=\frac{dv}{dt}$ , so:

$F=m*\frac{dv}{dt}\\\frac{dv}{dt}=\frac{F}{m}=\frac{\frac{1}{2}(t+1)}{4}=\frac{t+1}{8}$

The next step is separate variables and integrate (the limits are at this way because at t=0 the block was at rest (v=0):

$dv=\frac{1}{8}(t+1)dt\\\int\limits^{v_{2}}_0 \, dv=\int\limits^{2}_{0} {\frac{1}{8}(t+1)} \, dt$

$v_{2}=\frac{1}{8}*(\frac{t^{2}}{2}+t)$ (This is the indefinite integral), the definite one is:

$v_{2}=\frac{1}{8}*(2+2)=\frac{1}{2}$

3 0

3 years ago

A pure substance has a/an

Evgesh-ka [11]

Answer:

Element or a compound.

Explanation:

6 0

3 years ago