Answer:
d²x/dt² = - 4dx/dt - 4x is the required differential equation.
Explanation:
Since the spring force F = kx where k is the spring constant and x its extension = 2.45 equals the weight of the 4 kg mass,
F = mg
kx = mg
k = mg/x
= 4 kg × 9.8 m/s²/2.45 m
= 39.2 kgm/s²/2.45 m
= 16 N/m
Now the drag force f = 16v where v is the velocity of the mass.
We now write an equation of motion for the forces on the mass. So,
F + f = ma (since both the drag force and spring force are in the same direction)where a = the acceleration of the mass
-kx - 16v = 4a
-16x - 16v = 4a
16x + 16v = -4a
4x + 4v = -a where v = dx/dt and a = d²x/dt²
4x + 4dx/dt = -d²x/dt²
d²x/dt² = - 4dx/dt - 4x which is the required differential equation
C. 10 m/s
You divide 1000 m by 100 s.
1000/100 to find the velocity
Answer:
Explanation:
During a car collision momentum of vehicle ceases within a fraction of seconds so Force due to the impulse is huge.
Impulse is defined as the product of average force and time. If we can increase the period of collision for the same impulse then the average force imparted will be less.
If we can increase the time period then damage due to collision will be less.
Answer:
option A
Explanation:
given,
height of the drop of stone = 9.44 m
speed of the stone = ?
As the stone is dropped the energy of the stone will be conserved.
using conservation of energy.
Potential energy = Kinetic energy

v = 13.60 m/s
Hence, the correct answer is option A
The safety items such as eye washing station, fire blanket, and the class shower.