Answer:
the charge per unit area on the plastic sheet is - 3.23 x 10⁻⁷ C/m²
Explanation:
given information:
styrofoam mass, m = 16 g = 0.016 kg
net charge, q = - 8.6 μC
to calculate the charge per unit area on the plastic sheet, we can use the following equation:
where
the force between the electric field
m = mass
g = gravitational force
where
q = charge
E = electric field
and
E = σ/2ε₀
where
ε₀ = permitivity
thus
mg = qσ/2ε₀
σ = (2mg ε₀)/q
= 2 (0.016) (9.8) (8.85 x 10⁻¹²)/( - 8.6 x 10⁻⁶)
= - 3.23 x 10⁻⁷ C/m²
C: reflected
because the sun shines on the water when u look into the water u can see the sun
Answer: D
Height of marble from ground
Explanation:
From the formula of kinetic energy and potential energy,
K.E = 1/2mv^2
While
P.E = mgh
From all the parameters given from the question. You can see that mass is constant, acceleration due to gravity is also constant.
Independent variable must be a value that can varies.
Since Jack rolled a marble down a ramp and recorded the potential energy and kinetic energy of the marble at different positions on the ramp to see the effects on both energies.
This different position must be the height which will produce an effect on the potential and kinetic energy of the marble.
Independent variable always provides an effect for dependent variable. Which are kinetic energy and potential energy in this case.
Height of marble from ground is the right answer.
Answer:
a)
1.35 kg
b)
2.67 ms⁻¹
Explanation:
a)
= mass of first body = 2.7 kg
= mass of second body = ?
= initial velocity of the first body before collision = 
= initial velocity of the second body before collision = 0 m/s
= final velocity of the first body after collision =
using conservation of momentum equation
Using conservation of kinetic energy
b)
= mass of first body = 2.7 kg
= mass of second body = 1.35 kg
= initial velocity of the first body before collision = 4 ms⁻¹
= initial velocity of the second body before collision = 0 m/s
Speed of the center of mass of two-body system is given as
ms⁻¹
The answer would be 54 m/s as the maximum speed
