Answer:
a) 35.75 ft/s
b) 45 ft
Explanation:
<u>Given </u>
Weight W = 100 lbf
mass(m) = 100*32.174/32.2=99.92 lb
decrease in kinetic energy ΔKE = -500 ft.lbf
increase in kinetic energy ΔPE= 1500 ft.lbf
initial velocity V_1 = 40 ft/s
initial height h_1 = 30 ft/s
The gravitational acceleration g = 32.2 ft/s2 Required
(a) Final velocity V_2 (a) Final elevation h_2
<u>Solution </u>
Change in kinetic energy is defined by
ΔKE = .5*m *( V_2 ^2-V_1^2)
Change in potential energy is defined by
ΔKE = W *( h_2 -h_1 )
Then,
-500=.5*99.92*1/32.174*(V_2 ^2-40^2)
V_2=35.75 ft/s
1500 = 100 x (h_2 — 30)
h_2= 45 ft
Net force on the image is 0 Newton.
<h3>What is force?</h3>
A force is an effect that can alter an object's motion according to physics. An object with mass can change its velocity, or accelerate, as a result of a force. An obvious way to describe force is as a push or a pull. A force is a vector quantity since it has both magnitude and direction.
Net upward force is balanced by net downward force so net force is zero.
Net force on the image is 0 Newton.
To learn more about force refer to the link:
brainly.com/question/13191643
#SPJ1
S= 1/2 x 182 x t = 1688.3
t = 1688.3 / 91
time = 18.55 seconds
Answer:
200 million years
Explanation:
The equation that describes the decay of a radioactive isotope is
where
is the amount of radioactive isotope left at time t
is the initial amount of isotope
is the half-life of the sample
In this problem, the ratio between unstable isotope and daughter isotope is 1:15; this means that
Because the "total proportion" of original sample was 1+15=16.
Also we know that the half-life is
So we can re-arrange the equation to find t, the age of the rock:
So, 200 million years.
