Answer:
(a) The average speed is 0.85 milles/minute
(b) The average velocity is zero
Explanation:
In order to answer part (a) and (b) you have to apply the formulas for average speed and average velocity which are:
<em>-Average speed formula:</em>
where d is the total distance traveled and t is the tota time
Replacing the given values:
milles/minute
Notice that you have to replace the total distance, which is 14 milles for the go plus 14 milles for the return. The same for the total time.
<em>-Average velocity formula:</em>
V = Δx/Δt
Where V is the velocity vector, Δx is the displacement and Δt is the change in time
V= 
Where X2 is the final position and X1 is the initial position
In this case X1= 0 i and X2=0 i (i is the unit vector in the x direction). So, the displacement is zero.
Therefore, the average velocity is:
V= 0 i [milles/minute]
Its acceleration is 10ft/ sec
Answer:
Explanation:
mass of object, m = 3 kg
spring constant, K = 750 n/m
compression, x = 8 cm = 0.08 m
angle of gun, θ = 30°
(a) As the ball is launched, it has some velocity due to the compression in the spring, so it has some kinetic energy.
(b) Let v be th evelocity of ball at the tim eof launch.
by using the conservation of energy
1/2 Kx² = 1/2 mv²
750 x 0.08 x 0.08 = 3 x v²
v = 1.265 m/s
By use of the formula of maximum height
h = 0.02 m
h = 2 cm
Answer:
The answer is 1.87nm/s.
Explanation:
The 
water loss must be replaced by of sap. 110g of sap corresponds to a volume of
thus rate of sap replacement is
The volume of sap in the vessel of length 
is
,
where 
is the cross sectional area of the vessel.
For 2000 such vessels, the volume is
taking the derivative of both sides we get:
on the left-hand-side 
is the velocity 
of the sap, and on right-hand-side 
; therefore,
and since the cross-sectional area is
;
therefore,
solving for we get:
which is the upward speed of the sap in each vessel.
