Answer:
A.) 1.3 seconds
B.) 0.42 m
Explanation:
A.) You are given the angle of projection to be 40 degrees and initial velocity of 20m/s.
At vertical component
U = Usin 40 that is,
U = 20sin40
Using the first equation of motion under gravity
V = U - gt
Let V = 0
0 = UsinØ - gt
gt = UsinØ
t = UsinØ/g
Where U = 20 m/s
Ø = 40 degree
g = 9.8 m/s^2
Substitutes all the parameters into the formula
t = 20sin40/9.8
t = 1.3 seconds
Total time of flight T = 2t
T = 2 × 1.3 = 2.6 s
B.) To calculate the maximum height,
You will use the formula
V^2 = U^2 - 2gH
At maximum height, V = 0
2gH = Usin^2Ø
H = Usin^2Ø/ 2g
Substitutes all the parameters into the formula
H = 20 sin^2(40) ÷ 2(9.8)
H = 8.2635/19.6
H = 0.42 m
Answer:C
Explanation:
Power=280watts=280/1000 kilowatts
Power=0.28 kilowatts
Device use 0.28 kilowatts in 1 day
1day=24hours
Device use 0.28 kilowatts in 24hours
30days=30 x 24=720 hours
For 720 hours=(0.28x720) ➗ 24
For 720 hours=201.6 ➗ 24
For 720 hours=8.4
Answer: vf1/vf2= 1/ sqrt(2)
Explanation :on the moon no drag force so we have only the force of gravity. aceleration is g(moon)= 1.62m/s2.the rest is basic kinematics
if the rock travels H to the bottom we can calculate velocity:
vo=0m/s (drops the rock) , yo=0
vf*vf= vo*vo+2g(y-yo)
when the rock is halfway y = H/2 so:
vf1*vf1=2*g*H/2 so vf1 = sqrt(gH)
when the rock reach the bottom y=H so:
vf2*vf2=2*g*H so vf2 = sqrt(2gH)
so vf1/vf2= 1/ sqrt(2)
good luck from colombia
It is a reflecting telescope and a compound microscope. I know this for sure