Answer:
8 N
Explanation:
Using the equation F=ma (F: force/ m: mass in kg/ a: acceleration),
F = (800/1000)(10)
F = 8 N
<span>5.7 km/h north and 5.8 km/h west are instantaneous velocities, while 8.1 km/h is the average velocity.
This is because each value has a magnitude and direction so it is a velocity. Moreover, the 8.1 km/h is the resultant of the two velocities so it is the average while the other two are instantaneous.</span>
Explanation:
If force or distance is increased, then amount of workdone will also increase.
Answer:
C.Vacuum
Explanation:
There are three methods of transfer of heat:
1) Conduction: conduction is the transfer of heat by direct contact between the molecules of two objects (or two substances). The particles of the hotter object vibrate faster than the particles of the colder object, so energy is transferred by collisions of the molecules from the hotter object to the colder object.
2) Convection: convection is the transfer of heat by mass movement of molecules. This occurs in fluids (liquids or gases), when an external source of heat is applied to the fluid. As a result, the part of the fluid closer to the source gets warmer, so it becomes less dense and rises, while the colder part sinks and replaces the hotter part, forming a convective current. The process continues until the heat source is removed.
3) Radiation: radiation is the transfer of heat carried by electromagnetic waves. Electromagnetic waves can travel in any medium and in a vacuum, so they are the only type of heat transfer that can occur in a vacuum (while conduction and convection cannot occur in a vacuum).
Answer:
(a) -1.18 m/s
(b) 0.84 m/s
Explanation:
(a)
The total linear momentum before the lumberjack begins to move is zero because all parts of the system are at res
From the law of conservation of momentum
m1v1+m2v2=0 hence m1v1=-m2v2 where m1 is mass of lumberjack, v1 is velocity of lumberjeck, m2 is mass of floating log, v2 is velocity of the floating log.
Substituting M1 for 103 Kg, V1 for 2.93 m/s, M2 for 255 Kg into the above equation we obtain
103Kg*2.93 m/s=-255Kg*V2
V2=-(103 kg*2.93 m/s)/255=-1.183490196 m/s
Hence V2=-1.18 m/s
(b)
For the second log
V(M1+M2)=m1v1 where V is the common velocity
V(103 Kg+255 Kg)=103 Kg*2.93 m/s
V=(103 Kg*2.93 m/s)/(103 Kg+255 Kg)=0.842988827 m/s
V=0.84 m/s
