Answer: horizontal speed is 3.9 m/s
Explanation: when ball starts to drop, its vertical speed v0 is zero.
We can calculate dropping time from s = v0t +0.5gt².
Dropping time t= √(2s/g)= √((2·8.0 m)/9.81 m/s²)= 1.277 s
Because ball travels horizontal distance s= 5.0 m
HorizontalSpeed v = s/t = 5.0 m/1.277s= 3,915 m/s
Answer:
C 350W
Explanation:
Given power output to walk on a flat ground to be 300W, h = 0.05x, v = 1.4m/s
m = 70kg and g =9.8m/s².
x = horizontal distance covered
Total energy used = potential energy used in climbing and the energy used in a walking the horizontal distance.
E = mgh + 300t
Where t is the time taken to cover the distance
x = vt and h = 0.05vt
So
E = mg×0.05×vt + 300t
Substituting respective values
E = 70×9.8×0.05×1.4t +300t = 348t
P = E/t = 348W ≈ 350W.
Answer:
22J
Explanation:
Given :
radius 'r'= 3cm
rotational inertia 'I'=4.5 x
kgm²
mass on one side of rope '
'= 2kg
mass on other side of rope'
' =4kg
velocity'v' of mass
' = 2m/s
Angular velocity of the pulley is given by
ω = v /r => 2/ 3x 
ω = 66.67 rad/s
For the rotating body, we have
KE =
I ω²

= 10J
Next is to calculate kinetic energy of the blocks :

=12J
Therefore, the total kinetic energy will be
KE =
=10 + 12
KE= 22J
Isn't velocity Distance over time? if the degree isn't adding resistance it should be 4000 ÷ 20 which gives you 200mps ("per second") which is the velocity without resistance.