Answer:
Explanation:
change in momentum = m ( v - u ) ; m is mass , V is final velocity and u is initial velocity .
= 250 ( 28 - 6 )
= 5500. N.s
for calculating magnitude of force we shall apply the concept of impulse
Impulse = F X t = m( v-u ) ; F is force applied for time t .
F x 60 = 5500
F = 91.67 N .
force exerted = 91.67 N .
Answer:
162.8 K
Explanation:
initial current = io
final current, i = io/8
Let the potential difference is V.
coefficient of resistivity, α = 43 x 10^-3 /K
Let the resistance is R and the final resistance is Ro.
The resistance varies with temperature
R = Ro ( 1 + α ΔT)
V/i = V/io (1 + α ΔT )
8 = 1 + 43 x 10^-3 x ΔT
7 = 43 x 10^-3 x ΔT
ΔT = 162.8 K
Thus, the rise in temperature is 162.8 K.
Answer:
Explanation:
Electric field E = 4 x 10⁷ V / m
Dielectric constant k = 24
capacitance of capacitor
C = kε₀ A / d
d = plate separation
A = plate area
C = .89 x 10⁻⁶
V / d = electric field
for minimum d , electric field will be maximum
V / d = 4 x 10⁷
1930 / d = 4 x 10⁷
d = 1930 / 4 x 10⁷
d = 482.5 x 10⁻⁷ m
= 48.25 x 10⁻⁶ m
C = kε₀ A / d
.89 x 10⁻⁶ = 24 ε₀ A / d
A = .89 x 10⁻⁶ X d / 24 ε₀
A = .89 x 10⁻⁶ X 48.25 x 10⁻⁶ / 24 x 8.85 x 10⁻¹²
= 42.9 / 212.4
= .2019 m²