Answer:
The kinetic energy of the wagon is 967.0 J
Explanation:
Given that,
Force = 120 N
Mass = 55 kg
Height = 8 m
We need to calculate the kinetic energy of the wagon
Using newtons law



Using equation of motion

Where,
v = final velocity
u = initial velocity
s = height
Put the value in the equation


Now, The kinetic energy is



Hence, The kinetic energy of the wagon is 967.0 J
Answer:2t
Explanation:
Given
Jason throwing watermelon at speed v and it spend t time in air
time to reach max height

0=v-gt'

and time to reach bottom is also t'
t=2t'

For guy throws his watermelon at speed 2v
So total time in air will be


t''=2t
Answer:
The focal length of the appropriate corrective lens is 35.71 cm.
The power of the appropriate corrective lens is 0.028 D.
Explanation:
The expression for the lens formula is as follows;

Here, f is the focal length, u is the object distance and v is the image distance.
It is given in the problem that the given lens is corrective lens. Then, it will form an upright and virtual image at the near point of person's eye. The near point of a person's eye is 71.4 cm. To see objects clearly at a distance of 24.0 cm, the corrective lens is used.
Put v= -71.4 cm and u= 24.0 cm in the above expression.


f= 35.71 cm
Therefore, the focal length of the corrective lens is 35.71 cm.
The expression for the power of the lens is as follows;

Here, p is the power of the lens.
Put f= 35.71 cm.

p=0.028 D
Therefore, the power of the corrective lens is 0.028 D.
Answer:
5.01 J
Explanation:
Info given:
mass (m) = 0.0780kg
height (h) = 5.36m
velocity (v) = 4.84 m/s
gravity (g) = 9.81m/s^2
1. First, solve for Kinetic energy (KE)
KE = 1/2mv^2
1/2(0.0780kg)(4.84m/s)^2 = 0.91 J
so KE = 0.91 J
2. Next, solve for Potential energy (PE)
PE = mgh
(0.0780kg)(9.81m/s^2)(5.36m) = 4.10 J
so PE = 4.10 J
3. Mechanical Energy , E = KE + PE
Plug in values for KE and PE
KE + PE = 0.91J + 4.10 J = 5.01 J
Recall the equation for magnetic force:
F = qv x B *x is cross product, not separate variable!
If the magnetic field points towards N and you throw E, then the magnetic force would point up, or out of the page. Use the right-hand rule. You point your finger towards the direction of the object, and curl your finger to the magnetic field. Your thumb is the direction of the magnetic force.
Hope this helps!