Answer:
The change in the mass of box = 0.01 kg
Volume of air in the polythene bag = Volume of air in the rigid box
Therefore, Volume of air in the box = 0.008 m^3
Now, Density = Mass/ Volume
=> Density = 0.01 / 0.008 = 1.25 Kg / m^3
Explanation:
I looked it up
Ox:vₓ=v₀
x=v₀t
Oy:y=h-gt²/2
|vy|=gt
tgα=|vy|/vₓ=gt/v₀=>t=v₀tgα/g
y=0=>h=gt²/2=v₀²tg²α/2g=>tgα=√(2gh/v₀²)=√(2*10*20/24²)=√(400/576)=0.83=>α=tg⁻¹0.83=39°
cosα=vₓ/v=v₀/v=>v=v₀/cosα=24/cos39°=24/0,77=31.16 m/s
Ec=mv²/2=2*31.16²/2=971.47 J=>Ec≈0.97 kJ
Answer:
The value of the spring constant of this spring is 1000 N/m
Explanation:
Given;
equilibrium length of the spring, L = 10.0 cm
new length of the spring, L₀ = 14 cm
applied force on the spring, F = 40 N
extension of the spring due to applied force, e = L₀ - L = 14 cm - 10 cm = 4 cm
From Hook's law
Force applied to a spring is directly proportional to the extension produced, provided the elastic limit is not exceeded.
F ∝ e
F = ke
where;
k is the spring constant
k = F / e
k = 40 / 0.04
k = 1000 N/m
Therefore, the value of the spring constant of this spring is 1000 N/m
The frictional force will be 0.22N.
<h3>What is Frictional force?</h3>
Frictional force is the force generated between two surfaces that are in contact and slide against each other.
Given,
Weight=4N
mass =4.9/9.8=0.5kg
Hieght =30m
velocity=24m/s
Acceration , v²-u²=2as
24²/2×30 =a , u is zero
a= 1.5m/s²
By Using conservation of energy ,
30F+1/2mv²=mgh
30F=1150-144
F= 6/30
F=0.2N
The force will be 0.2N
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Answer:
Mg and HCl
Explanation:
Here, we want to get the combination that could be used in the production of the needed hydrogen
An important chemical property of inorganic acids is that when they react with metals, they give off hydrogen gas in conjunction with the formation of a salt
HCl is a mineral acid while Mg is a metallic substance
So the reaction between this metal and the mineral acids will give the needed hydrogen gas to be produced
