When plane is going towards Halifax the speed of wind is in the direction of fly
so overall the net speed of the plane will increase
while when he is on the way back the air is opposite to flight so net speed will decrease
now the total time of the journey is 13 hours
out of this 2 hours he spent in mathematics talk
so total time of the fly is 13 - 2 = 11 hours
now we have formula to find the time to travel to Halinex

time taken to reach back

now we have total time


here d= 3000 miles



solving above quadratic equation we will have

so speed of plane will be 550 mph
Answer : The restoring force is directly proportional to the displacement of the block.
Explanation :
Restoring force is defined as the force that is exerted by the spring due to its mass.
Mathematically, the restoring force can be written as :

F = - k x
where,
k is the spring constant.
x is the displacement caused due to the mass.
Negative sign shows that the force is acting in opposite direction.
So, it is clear that the restoring force is directly proportional to the displacement of the block.
Hence, the correct option is (b) " The restoring force is directly proportional to the displacement of the block ".
For the answer to the question above,
<span>Q = amount of heat (kJ) </span>
<span>cp = specific heat capacity (kJ/kg.K) = 4.187 kJ/kgK </span>
<span>m = mass (kg) </span>
<span>dT = temperature difference between hot and cold side (K). Note: dt in °C = dt in Kelvin </span>
<span>Q = 100kg * (4.187 kJ/kgK) * 15 K </span>
<span>Q = 6,280.5 KJ = 6,280,500 J = 1,501,075.5 cal</span>
Answer:
The magnitude of the acceleration of the box is 2 m/s².
Explanation:
Given:
Mass of the box,
kg
Force acting towards east,
N
Frictional force acting towards west,
N
Let the acceleration be
m/s².
Now, net force acting on the box towards east is given as:

From Newton's second law of motion,

Therefore, the magnitude of the acceleration of the box is 2 m/s².