Answer:
1) Q ’= 8 Q
, 2) q ’= 16 q
, 3) r ’= ¾ r
Explanation:
For this exercise we will use Coulomb's law
F = k q Q / r²
It asks us to calculate the change of any of the parameters so that the force is always F
Original values
q, Q, r
Scenario 1
q ’= 2q
r ’= 4r
F = k q ’Q’ / r’²
we substitute
F = k 2q Q ’/ (4r)²
F = k 2q Q '/ 16r²
we substitute the value of F
k q Q / r² = k q Q '/ 8r²
Q ’= 8 Q
Scenario 2
Q ’= Q
r ’= 4r
we substitute
F = k q ’Q / 16r²
k q Q / r² = k q’ Q / 16 r²
q ’= 16 q
Scenario 3
q ’= 3/2 q
Q ’= ⅜ Q
we substitute
k q Q r² = k (3/2 q) (⅜ Q) / r’²
r’² = 9/16 r²
r ’= ¾ r
The reason why a delivery truck filled with birds sitting on the floor be heavier than a truck with the same birds flying around is because when the birds are sitting on the floor, they are adding their weight to the truck.
Meanwhile, if the birds are flying around they aren't resting on the truck or touching it, so therefore their weight wouldn't be added to the truck.
The mass of the truck will remain the same as you cannot change the mass but the weight will vary depending on the items and objects placed in it.
Answer:
d ) is the answer.
Explanation:
Let M be the mass and R be the radius of each of ball , hoop and disc.
kinetic energy of sphere - 1/2 MV² + 1/2 I ω² ,ω is angular velocity and
V = ωR
kinetic energy of sphere - 1/2 MV² + 1/2 x 2/5 MR² ω²
= 1/2 MV² + 1/5 MR² ω²
MV² ( 1/2 + 1/5 )
= .7 MV²
kinetic energy of Disk - 1/2 MV² + 1/2 I ω² ,ω is angular velocity and
V = ωR
kinetic energy of Disk - 1/2 MV² + 1/2 x 1/2 MR² ω²
= 1/2 MV² + 1/4 MR² ω²
MV² ( 1/2 + 1/4 )
= .75 MV²
kinetic energy of Hoop - 1/2 MV² + 1/2 I ω² ,ω is angular velocity and
V = ωR
kinetic energy of hoop - 1/2 MV² + 1/2 MR² ω²
= 1/2 MV² + 1/2 MR² ω²
MV² ( 1/2 + 1/2 )
= MV²
Kinetic energy is largest in case of hoop and least in case of sphere . So hoop will go up to the highest point and sphere will go to a height which will be least among the three.
<h2>
Impulse = 4.9 kgm/s</h2>
Explanation:
Impulse is given by change of momentum.
Mass of softball = 0.49 kg
Initial velocity of softball = 13 m/s
Initial momentum = 0.49 x 13 = 6.37 kgm/s
Final velocity of softball = 23 m/s
Final momentum = 0.49 x 23 = 11.27 kgm/s
Change of momentum = Final momentum - Initial momentum
Change of momentum = 11.27 - 6.37
Change of momentum = 4.9 kgm/s
Impulse = Change of momentum
Impulse = 4.9 kgm/s