Answer:
0.001152m
Explanation:
Linear expansivity of a material is the change in length of the material per unit length per degree rise in temperature. Mathematically,
¢ = ∆L/L1∆°C
¢ is the linear expansivity of the material = 12 x 10⁻⁶ °C⁻¹
Where ∆L is the change in length = L2-L1
L2 is the final length = ?
L1 is the initial length = 12m
∆°C is the change in temperature = °C2 - °C1 = 50-(-30) = 80°C
Substituting this values inside the formula to get the final length L2 after expansion, we have;
12 x 10⁻⁶ °C⁻¹ = L2-12/12×80
12 x 10⁻⁶ °C⁻¹ = L2-12/960
L2-12= 960×12 x 10⁻⁶ °C⁻¹
L2-12 = 0.001152
L2 = 12+0.001152
L2 = 12.001152m
Expansion will be the change in length L2-L1 = 12.001152-12
= 0.001152m
The expansion cracks between the slabs should be 0.001152m wide to prevent buckling
Answer:
a) 
b) 
Explanation:
Given:
- mass of the body,

- mass of the tyre,

- length of hanging of tyre,

- distance run by the body,

- acceleration of the body,

(a)
Using the equation of motion :
..............................(1)
where:
v=final velocity of the body
u=initial velocity of the body
here, since the body starts from rest state:

putting the values in eq. (1)


Now, the momentum of the body just before the jump onto the tyre will be:



Now using the conservation on momentum, the momentum just before climbing on the tyre will be equal to the momentum just after climbing on it.



(b)
Now, from the case of a swinging pendulum we know that the kinetic energy which is maximum at the vertical position of the pendulum gets completely converted into the potential energy at the maximum height.
So,



above the normal hanging position.
Answer:
Minimum time = 1.95x10^-4 s
Number of pulses = 5128.21 pulses/s
Explanation:
We have the speed of sound waves through human tissue with a value of 1540 m/s, to calculate the time it takes for the pulse to travel a distance of 30 cm (since the pulse will first travel a distance of 15 cm and then it will return another 15 cm to be detected by the equipment), therefore, the time between the two pulses will be equal to:
tminimum = 0.30 m/1540 m/s = 1.95x10^-4 s
To calculate the number of pulses, one second must be divided over the minimum time between the two pulses, as follows:
npulses = 1 s/1.95x10^-4 s = 5128.21 pulses/s
Animals will then have to adapt to their new environment. they might have to change their diet and get new homes.
Force is the interaction that changes the motion of an object. If we want to make a jump, our legs have to exert a force to the ground (or launch points), so that we can gain an equal and opposite force that changes our motion from being static on the ground to moving forward.