Answer:
t = 4.17 [s]
Explanation:
We know that work is defined as the product of force by distance.
W = F*d
where:
F = force [N] (units of Newtons)
d = distance = 6.34 x 10⁴ [mm] = 63.4 [m]
In order to find the force, we must determine the weight of the box, the weight can be determined by means of the product of mass by gravitational acceleration.
w = m*g
where:
m = mass = 1.47 x 10⁴ [g] = 14.7 [kg]
g = gravity acceleration = 9.81 [m/s²]
w = 14.7*9.81
w = 144.2 [N]
Therefore the work can be calculated.
W = w*d
W = 144.2*63.4
W = 9142.72 [J] (units of Joules)
Power is now defined in physics as the relationship of work at a given time
P = W/t
where:
P = power = 2190 [W]
t = time [s]
Now clearing t, we have.
t = W/P
t = 9142.72/2190
t = 4.17 [s]
Answer:
Part a)

Part b)

Explanation:
Part a)
Electric field due to large sheet is given as







now the electric field is given as


Part b)
Now since the electric field is required at same distance on other side
so the field will remain same on other side of the plate

Answer:
7.894 Hours.
Explanation:
Based on information number hours that this battery will last with give load has mathematical relation of.

with load 60A t = 1h, 30A t = 2h so on and forth.
two head lights draw total current of 2x3.8A = 7.6A.
putting this in above relation gives.
.
That is how long will it be before battery is dead.
Answer:
Speed = 0.296m/2
Period = 0.203 s
Explanation:
If by 'long' you mean the wavelength of the waves, then the wavelength
.
The frequency
of the waves is 14.8 waves every 3 seconds or
.
Now the relationship between wavelength
, frequency
and speed
of the waves is:

We put in the values
and
and get:
Now the period
is just the inverse of the frequency, or


As we know by the formula of bulk modulus

now we can rearrange it as


now the final volume after pressure is applied is given as

now we know that



now plug in all data


so volume is above after pressure is applied over it