Answer:
$900
Explanation:
Step 1: Our output value is 9000.
Step 2: We represent the unknown value with x.
Step 3: From step 1 above,$9000=100\%$
Step 4: Similarly, x=10%
Step 5: This results in a pair of simple equations:
$9000=100
Step 6: By dividing equation 1 by equation 2 and noting that both the RHS (right hand side) of both
equations have the same unit (%); we have
\frac{9000}{x}=\frac{100\%}{10\%}
Step 7: Again, the reciprocal of both sides gives
\frac{x}{9000}=\frac{10}{100}$
\Rightarrow x=900$
Therefore, $10\%$ of $9000$ is $900$
Answer: a) B = 6811N
b) m = 603.2kg
c) 86.8%
Explanation: <em>Buoyant force</em> is a force a fluid exerts on a submerged object.
It can be calculated as:

where:
is density of the fluid the object is in;
is volume of the object;
g is acceleration due to gravity, is constant and equals 9.8m/s²
a) For the hollow plastic sphere, density of water is 1000kg/m³:

B = 6811N
b) Anchored to the bottom, the forces acting on the sphere are <u>Buoyant</u>, <u>Tension</u> and <u>Force due to gravity</u>:
B = T + 
B = T + mg
mg = B - T

Calculating:

m = 603.2kg
c) When the shpere comes to rest on the surface of the water, there are only <u>buoyant</u> <u>and</u> <u>gravity</u> acting on it:
B = m.g



= 0.6032m³
Fraction of the submerged volume is:
=
= 0.868
<u />
Answer:
2.55 m
Explanation:
Elastic energy = gravitational energy
½ kx² = mgh
h = kx² / (2mg)
h = (200 N/m) (0.05 m)² / (2 × 0.010 kg × 9.8 m/s²)
h = 2.55 m
Because it generates enough momentum to keep the train going with out really having to speed up
Answer:
electrons
Explanation:
The total charge Q is the sum of the charge of the N electrons contained in the sphere:

charge of a electron
We solve to find N:
