6. f = 128.62
, T= 0.0077775 s
7. f = 2.2 *
, T = 4.545 *
s
8. 32.64 
9. 3.29 *

Explanation:
Step 1:
6.
For light and sound v = fλ
where v represents the velocity
f represents the frequency
λ represents the wavelength
λ = 2.69 m
v = 346 m/s
f = v/λ = 346/2.69 = 128.62 
Time period is the reciprocal of frequency
T = 1/128.62 = 0.0077775 s
Step 2:
7.
λ = 110 cm = 1.1 m
v = 2.42*
m/s
f = 2.42*
/1.1 = 2.2 *

T = 1/(2.2*
) = 4.545 *
s
Step 3:
8.
λ = 10.6 m
v = 346 m/s
f = v/λ = 346/10.6 = 32.64 
Step 4:
9.
λ = 5.89 *
m
v = 1.94 *
m/s
f = v/λ = 3.29 *

Answer:
Part a)

Part b)

Explanation:
As we know that electric force on electric charge is given as

here we have

E = 153 N/C
now force is given as

Gravitational force on electric charge near surface of earth is given as


now the ratio of two forces is given as


Part b)
Now the ball is balanced by the electric force and the force of gravity on it
so here we have



here we have

Explanation:
(a)
Critical angle is the angle at the angle of refraction is 90°. After the critical angle, no refraction takes place.
Using Snell's law as:
Where,
is the angle of incidence
is the angle of refraction = 90°
is the refractive index of the refraction medium
is the refractive index of the incidence medium
Thus,
The formula for the calculation of critical angle is:
Where,
is the critical angle
(b)
No it cannot occur. It only occur when the light ray bends away from the normal which means that when it travels from denser to rarer medium.
Answer:
The magnitude of the current is 5.45 mA.
Explanation:
Given that,
Resistance = 10.0 ohm
Radius = 0.10 m
Magnetic field = 1.0 T
Angle = 30°
Increase magnetic field = 7.0 T
Time t = 3.0 s
Number of turns = 1
We need to calculate the initial flux
Using formula of flux

Put the value into the formula



We need to calculate the final flux


We need to calculate the induced emf
Using formula of emf

Put the value into the formula


We need to calculate the current
Using formula of current

Put the value into the formula


Hence, The magnitude of the current is 5.45 mA.
Answer:
<em>The mass of the apple is 0.172 kg (172 g)</em>
Explanation:
<u>The Law Of Conservation Of Linear Momentum
</u>
The total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and speed v is
P=mv.
If we have a system of two bodies, then the total momentum is the sum of both momentums:

If a collision occurs and the velocities change to v', the final momentum is:

Since the total momentum is conserved, then:
P = P'
Or, equivalently:

If both masses stick together after the collision at a common speed v', then:

We are given the mass of an arrow m1=43 g = 0.043 kg traveling at v1=84 m/s to the right (positive direction). It strikes an apple of unknown mass m2 originally at rest (v2=0). The common speed after they collide is v'=16.8 m/s.
We need to solve the last equation for m2:

Factoring m2 and m1:

Solving:

Substituting:



The mass of the apple is 0.172 kg (172 g)