Answer:
d) Law of Conservation of Energy
Explanation:
The first law of thermodynamics states that energy can neither be created nor destroyed; energy can only change from one form to another.
For multiple choice you can use an elimination method. If you remember the law then you know it's not A or C because "energy cannot be created nor destroyed", and it's not B because it has nothing to do with mass.
Hope this helps!
Answer:
A. Velocity
Explanation:
Velocity is vector quantity thus has both magnitude and direction. It describes not only the speed but also the direction. Speed is scalar quantity so describes only speed but not direction. Energy has nothing to do with speed, acceleration describes change in velocity in a direction over time
The equilibrium condition allows finding the result for the force that the chair exerts on the student is:
- The reaction force that the chair exerts on the student's support is equal to the student's weight.
Newton's second law gives the relationship between force, mass and acceleration of bodies, in the special case that the acceleration is is zero equilibrium condition.
∑ F = 0
Where F is the external force.
The free body diagram is a diagram of the forces on bodies without the details of the shape of the body, in the attached we can see a diagram of the forces.
Let's analyze the force on the chair.
Let's analyze the forces on the student.
In conclusion using the equilibrium condition we can find the result for the force that the chair exerts on the student is:
- The reaction force that the chair exerts on the student's support is equal to the student's weight.
Learn more here: brainly.com/question/18117041
Answer:
(a) T= 38.4 N
(b) m= 26.67 kg
Explanation:
We apply Newton's second law:
∑F = m*a (Formula 1)
∑F : algebraic sum of the forces in Newton (N)
m : mass in kilograms (kg)
a : acceleration in meters over second square (m/s²)
Kinematics
d= v₀t+ (1/2)*a*t² (Formula 2)
d:displacement in meters (m)
t : time in seconds (s)
v₀: initial speed in m/s
vf: final speed in m/s
a: acceleration in m/s²
v₀=0, d=18 m , t=5 s
We apply the formula 2 to calculate the accelerations of the blocks:
d= v₀t+ (1/2)*a*t²
18= 0+ (1/2)*a*(5)²
a= (2*18) / ( 25) = 1.44 m/s²
to the right
We apply Newton's second law to the block A
∑Fx = m*ax
60-T = 15*1.44
60 - 15*1.44 = T
T = 38.4 N
We apply Newton's second law to the block B
∑Fx = m*ax
T = m*ax
38.4 = m*1.44
m= (38.4) / (1.44)
m = 26.67 kg
