Answer:
Explanation:
How long does the football need to rise?
4.70/3 = 2.35 s
What height will the football reach?
h = ½(9.81)2.35² = 27.1 m
With what speed does the punter need to kick the football?
vy = g•t = 9.81(2.35) = 23.1 m/s
vx = d/t = 56.0/4.70 = 11.9 m/s
v = √(vx²+vy²) = 26.0 m/s
At what angle (θ), with the horizontal, does the punter need to kick the football?
θ = arctan(vy/vx) = 62.7°
Answer:
Explanation:
The gravitational potential energy gets transformed into translational and rotational kinetic energy, so we can write 
. Since 
(the ball rolls without slipping) and for a solid sphere 
, we have:
So our translational speed will be:
Answer:
2. west
Explanation:
Given an electron is moving vertically upward from ground.
Now Fleming right hand rule state that: make L shape with thumb and index finger then point middle finger perpendicular to index and thumb.Then index finger points in the direction of moving charge , middle finger points in the direction of the magnetic field and thumb points in the direction of the magnetic force.
According to Fleming right hand rule the direction of the magnetic that acts on the electron is west.
Answer:
Explanation:
a rigid object in uniform rotation about a fixed axis does not satisfy both the condition of equilibrium .
First condition of equilibrium is that net force on the body should be zero.
or F net = 0
A body under uniform rotation is experiencing a centripetal force all the time so F net ≠ 0
So first condition of equilibrium is not satisfied.
Second condition is that , net torque acting on the body must be zero.
In case of a rigid object in uniform rotation , centripetal force is applied towards the centre ie towards the line joining the body under rotation with the axis .
F is along r
torque = r x F
= r F sinθ
θ = 0 degree
torque = 0
Hence 2nd condition is fulfilled.
From the information given, cannon ball weighs 40 kg and has a potential energy of 14000 J.
We need to find its height.
We will use the formula P.E = mgh
Therefore h = P.E / mg
where P.E is the potential energy,
m is mass in kg,
g is acceleration due to gravity (9.8 m/s²)
h is the height of the object's displacement in meters.
h = P.E. / mg
h = 14000 / 40 × 9.8
h = 14000 / 392
h = 35.7
Therefore the canon ball was 35.7 meters high.
