Answer:If an object's speed changes, or if it changes the direction it's moving in,
then there must be forces acting on it. There is no other way for any of
these things to happen.
Once in a while, there may be a group of forces (two or more) acting on
an object, and the group of forces may turn out to be "balanced". When
that happens, the object's speed will remain constant, and ... if the speed
is not zero ... it will continue moving in a straight line. In that case, it's not
possible to tell by looking at it whether there are any forces acting on it
Answer:
Explanation:
The momentum of the 25 kg mass is
If this whole momentum of the object is transferred to the 5.0 kg object then according to the law of conservation of momentum, the momentum of the 25.0 kg object must be transferred to the 5.0 kg object:
Steam enters a cylinder—- A
Answer:
3.75 MeV
Explanation:
The energy of the photon can be given in terms of frequency as:
E = h * f
Where h = Planck's constant
The frequency of the photon is 6 * 10^20 Hz.
The energy (in Joules) is:
E = 6.63 x10^(-34) * 6 * 10^(20)
E = 39.78 * 10^(-14) J = 3.978 * 10^(-13) J
We are given that:
1 eV = 1.06 * 10^(-19) Joules
This means that 1 Joule will be:
1 J = 1 / (1.06 * 10^(-19)
1 J = 9.434 * 10^(18) eV
=> 3.978 * 10^(-13) J = 3.978 * 10^(-13) * 9.434 * 10^(18) = 3.75 * 10^(6) eV
This is the same as 3.75 MeV.
The correct answer is not in the options, but the closest to it is option C.
Answer:
970 kN
Explanation:
The length of the block = 70 mm
The cross section of the block = 50 mm by 10 mm
The tension force applies to the 50 mm by 10 mm face, F₁ = 60 kN
The compression force applied to the 70 mm by 10 mm face, F₂ = 110 kN
By volumetric stress, we have that for there to be no change in volume, the total pressure applied by the given applied forces should be equal to the pressure removed by the added applied force
The pressure due to the force F₁ = 60 kN/(50 mm × 10 mm) = 120 MPa
The pressure due to the force F₂ = 110 kN/(70 mm × 10 mm) = 157.142857 MPa
The total pressure applied to the block, P = 120 MPa + 157.142857 MPa = 277.142857 MPa
The required force, F₃ = 277.142857 MPa × (70 mm × 50 mm) = 970 kN
