Answer:
<em>k = 25.18 N/m</em>
Explanation:
<u>Simple Harmonic Oscillator</u>
It consists of a weight attached to one end of a spring being allowed to move forth and back.
If m is the mass of the weight and k is the constant of the spring, the period of the oscillation is given by:

If the period is known, we can find the value of the constant by solving for k:

Substituting the given values m=5 Kg and T=2.8 seconds:

k = 25.18 N/m
It's not possible to answer the question exactly the way it's written.
That's because we don't know anything about the direction they
drive at any time during the trip.
You see, "velocity" is not just a word that you use for 'speed' when
you want to sound smart and technical, like this question is doing.
"Velocity" is a quantity that's made up of speed AND THE DIRECTION
of the motion. If you don't know the direction of the motion, then you
CAN'T tell the velocity, only the speed.
Here are the average speeds that Lori's family drove on each leg
of their trip:
Speed = (distance covered) / (time to cover the distance) .
Leg-A:
Speed = 15km/10min = 1.5 km/min
Leg-B:
Speed = 20km/15min = (1 and 1/3) km/min
Leg-C
Speed = 24km/12min = 2 km/min
Leg-D:
Speed = 36km/9min = 4 km/min
Leg-E:
Speed = 14km/14min = 1 km/min
From lowest speed to highest speed, they line up like this:
[Leg-E] ==> [Leg-B] ==> [Leg-A] ==> [Leg-C] ==> [Leg-D]
1.0 . . . . . . . . 1.3 . . . . . . . 1.5 . . . . . . . 2.0 . . . . . . . 4.0 . . . . km/minute
Whoever drove Leg-D should have been roundly chastised
and then abandoned by the rest of the family. 36 km in 9 minutes
(4 km per minute) is just about 149 miles per hour !
Answer:
Current in the loop is 0.063 A
Explanation:
Number of turns in the coil N = 150
Radius of the circular loop r = 7.5 cm = 0.075 m
So area 
Magnetic field B = 1.5 T
Maximum torque is given 
We have to find current in the coil
Torque on circular coil in magnetic field is equal to


I = 0.063 A
Answer:
The correct option is C
Explanation:
According to third equation of motion, v
2
=u
2
+2ax
Here, u=0 m/s
a=−g and x=−h
Negative sign indicates downward direction. Displacement and acceleration both are downwards.
So,v=±
2(−g)(−h)
We take minus sign because it is downwards.
v=−
2gh
After bouncing. velocity becomes 80% of v, i.e.,
v
′
=+0.8
2gh
(positive sign because the direction of ball has reversed after bouncing and is upwards.
Applying third equation of motion again, for u=v
′
, v=0 and a=−g
v
2
=u
2
+2×a×x
Thus,
0=0.64(2gh)+2(−g)x
or
x=0.64h
False. A sound wave is an example of a mechanical wave, not an EM wave.
Hope this helps! :)