Answer:
0.90m/s²
Explanation:
Given parameters:
Initial speed = 6miles/hr
Final speed = 12miles/hr
Time taken = 3 seconds
Unknown:
Acceleration = ?
Solution:
Acceleration is the rate of change of velocity with time. It is mathematically given as:
Acceleration = 
We need to convert miles/hr to meters/seconds
Initial speed = 6 x
x
x 
= 2.68m/s
Final speed = 12 x
= 5.37m/s
Acceleration =
= 0.90m/s²
Answer:
a) P' = P_original, b) P ’= P_original + ρ g Δh
Explanation:
The expression for nanometric pressure is
P = ρ g h
where ρ is the density of the liquid and h is the height
a) we change the radius of the barrel, but keeping the same height
as the pressure does not depend on the radius it remains the same
P' = P_original
b) We change the barrel height
h ’≠ h
we substitute in the equation
P ’= ρ g h’
h ’= h + Δh
P ’= ρ g (h + Δh)
P ’= (ρ g h) + ρ g Δh
P ’= P_original + ΔP
In this case, the pressure changes due to the new height,
*if it is higher than the initial one, the pressure increases
*if the height is less than the initial one, the pressure is less
Answer:
83000000
Explanation:
Conversion factor: 1 kg = 100000 cg
1) Centigram = Kilogram * 100000
2) Centigram = 830 * 100000
3) Centigram = 83000000
~~Hope this helps~~
Answer:
B.The force of friction between the block and surface will decrease.
Explanation:
The force of friction is given by

where
is the coefficient of friction and
is the normal force.
When the student pulls on the block with force
at an angle
, the normal force on the block becomes

and hence the frictional force becomes
.
Now, as we increase
,
increases which as a result decreases the normal force
, which also means the frictional force decreases; Hence choice B stands true.
<em>P.S: Choice D is tempting but incorrect since the weight </em>
<em> is independent of the external forces on the block. </em>