Answer:
a) E = 0
b) 
Explanation:
The electric field for all points outside the spherical shell is given as follows;
a) 
From which we have;
E = 0/A = 0
E = 0
b)
By Gauss theorem, we have;
Therefore, we get;
The electrical field outside the spherical shell
Therefore, we have;
Answer:
Explanation:
a )
Reaction force of the ground
R = mg
= 160 N
Maximum friction force possible
= μ x R
= μ x 160
= .4 x 160
= 64 N .
b )
160 N will act at middle point . 740N will act at distance of 3 / 5 m from the wall ,
Taking moment about top point of ladder
160 x 1.5 + 740 x 3/5 + f x 4 = 900 x 3
240 + 444 + 4f = 2700
f = 504 N
c )
Let x be the required distance.
Taking moment about top point of ladder
160 x 1.5 + 740 x 3 x / 5 + .4 x 900 x 4 = 900 x 3 ( .4 x 900 is the maximum friction possible )
240 + 444 x + 1440 = 2700
x = 2.3 m
so man can go upto 2.3 at which maximum friction acts .
A = 1.15m/s2, Vf = 80.0km/h --> we need it in m/s, so:
Vf = 80km/h × 1000m/1km × 1h/3600s
= 22.22m/s
Top speed = Vf, initial speed = Vi
time (t) = V(Vf-Vi) ÷ a
t = (22.22-0)m/s ÷ 1.15m/s2
t = 22.22m/s × s2/1.15m
= 19.32 seconds
m₁ = mass of the first object = 3.0 kg
m₂ = mass of the second object = 3.0 kg
r = distance between the first and second object = 1.0 m
G = universal gravitational constant = 6.67 x 10⁻¹¹ N m²/kg²
F = force of gravity between the two objects = ?
according to law of gravitation, force of attraction "F" between two objects m₁ and m₂, placed distance "r" apart is given as
F = G m₁ m₂/r²
inserting the values
F = (6.67 x 10⁻¹¹) (3.0) (3.0)/(1.0)²
F = (6.67 x 10⁻¹¹) (9.0)
F = 60.03 x 10⁻¹¹ N
F = 6.003 x 10⁻¹⁰ N
