Answer:
speed of the mass is 3.546106 m / s
Explanation:
given data
mass = 77.3 g = 77.3 ×
kg
spring constant k = 12.5 N/m
amplitude A = 38.9 cm = 38.9 ×
m
to find out
the speed of the mass
solution
we will apply here conservation energy that is
K.E + P.E = Total energy ..................1
so that Total energy = K.E max = P.E max
we know amplitude so we find out first P.E max that is
PE max = K.E + P.E
(1/2)kA² = (1/2)mv² + (1/2)kx²
kA^² = mv²+ kx²
so here v² will be
v² = k(A² - x²) / m
v = √[(k/m)×(A² - x²)] ............2
here x = (1/2)A so from from 2 equation
v = √[(k/m)×(A² - (A/2)²)]
v = √[(k/m)×(3/4×A²)]
now put all value
v = √[(12.5/ 77.3 ×
)×(3/4×(38.9 ×
)²)]
v = 3.546106 m / s
speed of the mass is 3.546106 m / s
Answer:
5kgm
Explanation:
convert cm to m and g to kg
250/1000=0.25kg
5/1000=0.05m
then find the density
density=mass/volume
=0.25kg/0.05m
=5kgm
<span>Since the equation is F = ma the acceleration would change by a factor of 2, since a = v/2. The force would double.</span>
Answer: B
D makes no sense because energy is created so we can remove that. C also makes no sense because if energy is not created how did it get destroyed if there's no energy in the first place. This leaves us with a and B the correct answer is B because energy is created and cannot be destroyed.