Answer: 14.16
Explanation:
Given
d = 38cm
r = d/2 = 38/2 = 19cm = 0.19m
K.E = 510J
m = 10kg
I = 1/2mr²
I = 1/2*10*0.19²
I = 0.18kgm²
When it has 510J of Kinetic Energy then,
510J = 1/2Iω²
ω² = 1020/I
ω² = 1020/0.18
ω² = 5666.67
ω = √5666.67 = 75.28 rad/s
Velocity is the block, v = ωr
V = 75.28 * 0.19
V = 14.30m/s
The "effective mass" M of the system is
M = (14.0 + ½*10.0) kg = 19.0 kg
The motive force would be
F = ma
F = 14 * 9.8
F = 137.2N
so that the acceleration would be
a = F/m
a = 137.2/19
a = 7.22m/s²
Finally, using equation of motion.
V² = u² + 2as
14.3² = 0 + 2*7.22*s
204.49 = 14.44s
s = 204.49/14.44
s = 14.16m
194db is the loudest Sound wave
Answer:
7.2 cm
Explanation:
magnetic field, B = 0.301 T
speed, v = 7.92 x 10^5 m/s
mass, m = 4.39 x 10^-27 kg
q = 1.6 x 10^-19 C
The radius of singly changed ion is given by

where, m is the mass of ion, v be the speed of ion, B is the magnetic field and q be the charge

r = 0.072 m
r = 7.2 cm
<h2>
Speed of motorboat is 36 km/hr and speed of current is 4 km/hr.</h2>
Explanation:
Let speed of motor boat be m and speed of current be c.
A motorboat traveling with a current can go 160 km in 4 hours.
Distance = 160 km
Time = 4 hours
Speed = m + c
We have
Distance = Speed x Time
160 = (m+c) x 4
m + c = 40 --------------------- eqn 1
Against the current it takes 5 hours to go the same distance.
Distance = 160 km
Time = 5 hours
Speed = m - c
We have
Distance = Speed x Time
160 = (m-c) x 5
m - c = 32 --------------------- eqn 2
eqn 1 + eqn 2
2m = 40 + 32
m = 36 km/hr
Substituting in eqn 1
36 + c = 40
c = 4 km/hr
Speed of motorboat is 36 km/hr and speed of current is 4 km/hr.
Answer:
80 degress is needed to boil 200g of water from 30 degress