Let k = the force constant of the spring (N/m).
The strain energy (SE) stored in the spring when it is compressed by a distance x=0.35 m is
SE = (1/2)*k*x²
= 0.5*(k N/m)*(0.35 m)²
= 0.06125k J
The KE (kinetic energy) of the sliding block is
KE = (1/2)*mass*velocity²
= 0.5*(1.8 kg)*(1.9 m/s)²
= 3.249 J
Assume that negligible energy is lost when KE is converted into SE.
Therefore
0.06125k = 3.249
k = 53.04 N/m
Answer: 53 N/m (nearest integer)
F=ma
a=F/m
=825N/75kg
=825kg*m/75kg*s^2
=11m/s^2 in the direction of the force (ans)
<h3><u>Answer;</u></h3>
= 0.0000001 mol/L
= 0.0000001 mol/L
= 1:1
<h3><u>Explanation;</u></h3>
What is the concentration of H+ ions at a pH = 7?
The formula for ph is given by:
pH=−log10[H+]
In calculating for the concentration of hydrogen ion, the formula is given by:
[H+]=(10)^(-pH)
Therefore; at pH = 7
[H+]=(10)^(-7)
<u>= 0.0000001 mol/L </u>
What is the concentration of OH– ions at a pH = 7?
pH+pOH=14
7+pOH=14
pOH= 7
[OH-]=(10)^(-pOH)
[OH-]=(10)^(-7)
<u>= 0.0000001 mol/L </u>
What is the ratio of H+ ions to OH– ions at a pH = 7?
1:1
Force=mass*acceleration
F=ma
20=2.8a
a=20/2.8
a=7.14 m/s^2
