8.64
×10^4
this is 86400 in scientific notation
Answer:
31.404 seconds
Explanation:
To answer this equation, SUVAT is your best option utilizing and rearranging the known values to solve for the unknown.
here we have the values for
s=895
u=22
v=35
t= the unknown value
in this instant the equation s=0.5 x (u+v)t is the best equation to use
so we sub in the known values
895=0.5 x (22+35)t
rearrange to solve for t
895=28.5t
895/28.5=t
t=31.404 seconds (rounded to 3 decimal places)
Answer:
Tension in Cord=174 N
Explanation:
Given Data
L (Phone Cord Length)=4.89 m
m (Cord Mass)=0.212 Kg
T (Time for four trips)=0.617 s
Tension=?
Solution
V=λ×f



B) 14.0 N
The way to solve this problem is to determine the kinetic energy the box had before and after the rough patch of floor. The equation for kinetic energy is:
E = 0.5 M V^2
where
E = Energy
M = Mass
V = velocity
Substituting the known values, let's calculate the before and after energy.
Before:
E = 0.5 M V^2
E = 0.5 13.5kg (2.25 m/s)^2
E = 6.75 kg 5.0625 m^2/s^2
E = 34.17188 kg*m^2/s^2 = 34.17188 joules
After:
E = 0.5 M V^2
E = 0.5 13.5kg (1.2 m/s)^2
E = 6.75 kg 1.44 m^2/s^2
E = 9.72 kg*m^2/s^2 = 9.72 Joules
So the box lost 34.17188 J - 9.72 J = 24.451875 J of energy over a distance of 1.75 meters. Let's calculate the loss per meter by dividing the loss by the distance.
24.451875 J / 1.75 m = 13.9725 J/m = 13.9725 N
Rounding to 1 decimal place gives 14.0 N which matches option "B".