Answer:
a. 8.96 m/s b. 1.81 m
Explanation:
Here is the complete question.
a) A long jumper leaves the ground at 45° above the horizontal and lands 8.2 m away.
What is her "takeoff" speed v
0
?
b) Now she is out on a hike and comes to the left bank of a river. There is no bridge and the right bank is 10.0 m away horizontally and 2.5 m, vertically below.
If she long jumps from the edge of the left bank at 45° with the speed calculated in part a), how long, or short, of the opposite bank will she land?
a. Since she lands 8.2 m away and leaves at an angle of 45 above the horizontal, this is a case of projectile motion. We calculate the takeoff speed v₀ from R = v₀²sin2θ/g. where R = range = 8.2 m.
So, v₀ = √gR/sin2θ = √9.8 × 8.2/sin(2×45) = √80.36/sin90 = √80.36 = 8.96 m/s.
b. We use R = v₀²sin2θ/g to calculate how long or short of the opposite bank she will land. With v₀ = 8.96 m/s and θ = 45
R = 8.96²sin(2 × 45)/9.8 = 80.2816/9.8 = 8.192 m.
So she land 8.192 m away from her bank. The distance away from the opposite bank she lands is 10 - 8.192 m = 1.808 m ≅ 1.81 m
Answer:
90.78 rev/min
Explanation:
In first place, we have to do the force balance to determine the minimum angular speed required to avoid slipping. The forces acting here are friction and the force due to circular movement, that is centripetal force. Then, we have:
μmg=mRω^2
ω=
Then, replacing the given values in the expression we have the following result:
ω=1.51 rev/s*60s=90.78 rev/min
Answer:
Hey there!
For this question, we use the acceleration formula:
A=V/T
A=-50/10
A=-5 m/s/s
Let me know if this helps :)
Answer:
<h3>3.06s</h3>
Explanation:
If I drop a paper clip from rest and it falls freely until it hits the ground with a speed of 30 m/s,we ae to find the time taken for the ball to drop. To do that we will use the equation of motion v = u + gt
v is the final velocity = 30m/s
u is the initial velocity = 0m/s (the object drops from rest)
g is the acceleration due to gravity = 9.81m/s²
time is the time taken
Substituting the given parameters into the formula;
30 = 0 + (9.81)t
30 = 9.81t
t = 30/9.81
t = 3.06secs
<em></em>
<em>Hence it will take the object 3.06secs in free fall</em>
The answer to the first one is sublimation.