Answer:
1.) Time t = 3.1 seconds
2.) Height h = 46 metres
Explanation:
given that the initial velocity U = 30 m/s
At the top of the trajectory, the final velocity V = 0
Using first equation of motion
V = U - gt
g is negative 9.81m/^2 as the object is going against the gravity.
Substitute all the parameters into the formula
0 = 30 - 9.81t
9.81t = 30
Make t the subject of formula
t = 30/9.81
t = 3.058 seconds
t = 3.1 seconds approximately
Therefore, it will take 3.1 seconds to reach to reach the top of its trajectory.
2.) The height it will go can be calculated by using second equation of motion
h = ut - 1/2gt^2
Substitutes U, g and t into the formula
h = 30(3.1) - 1/2 × 9.8 × 3.1^2
h = 93 - 47.089
h = 45.911 m
It will go 46 metres approximately high.
Answer:
The absolute potential 4.0 m away from the same point charge is -50 V.
(A) is correct option.
Explanation:
Given that,
Distance = 2.0 m
Potential = -100 V
Absolute potential = 4.0 m
We need to calculate the charge
Using formula of potential
Where, V = potential
q = charge
r = distance
Put the value into the formula
We need to calculate the potential
Using formula of potential
Hence, The absolute potential 4.0 m away from the same point charge is -50 V.
The correct answer is C. She did no work because she did not move the scales or sword while she posed.
Explanation:
In physics, the term "work" is used to refer to the energy or force related to the displacement of an object. Indeed, this variable is calculated through the formula W (work) = F (force) x d (displacement). This implies, there is only work if there is displacement. According to this, Brandi did no work while posing because even if she used her force to hold the scales and sword she did not move and displacement is essential for work to exist. Thus, the correct option is C.
Answer:
By Gauss' Law the sphere will appear externally as if all of the charge were concentrated at the center of the sphere.
E = K Q / r^2 = K Q / .528^2
Q = 1710 * .528^2 / 9.00E9 Coulombs
Q = 5.30E-8 Coulombs on sphere
V = 4/3 π R^3 = 4/3 π * .384^3 = .237 m^3
ρ = Q / V = 5.30E-8 / .237 = 2.23E-7 C/m^3
At .223 from center Q = 4/3 π .223^3 * ρ (charge outside this radius will not affect electric field outside .223 m)
Q = 2.23E-7 * 4/3 * π * .223^3 = 1.04E-8 Coulombs
E = 9.00E9 * 1.04E-8 / .223^2 = 1880 N/C
Recall that the particles that make up matter are always moving. These particles have kinetic energy, the energy an object has due to its motion. The faster particles move, the more kinetic energy they have. Within a given substance, such as water, particles in the solid state have the least amount of kinetic energy. got it from this site http://www.ckrs.org/ckrs/About%20CKRS/Faculty%20Email%20and%20Web%20Pages/Mrs.%20Gail%20Grisi/GRADE%208%20PHYSICAL%20SCIENCE-Lessons%2CStudy%20Guides/%28Owls%29%20Reading%20essentials%20c.6-2%20Changes%20in%20State.pdf