Answer:
A
Explanation:
1. When the block moves across a table top, F(pulling) = - F(frictional).
Sum of this forces = 0, so the block moves with uniform speed.
2. When the block is pulled on top of the table covered with beads
F(pulling) > - F(frictional).
So, the sum of forces (∑F) is a number that is more than 0 and directed to the direction of movement.
So, a = ∑F / m is positive and constant. Speed is increasing because
v(t) = v(0)+at
a is constant and directed forward.
That means a is acceleration, and constant.
Fundamental States,
Non-classical States.
Solid,
Liquid,
Gas and
Plasma.
Answer:
B
Explanation:
there are three modes of heat transfer which are
- conduction
- convection
- radiation
Conduction is a mode of heat transfer in solid materials
Convection refers to a mode of heat transfer of fluids in motion.
Radiation occurs when heat moves as energy waves in form of infrared radiation. The energy from the sun reaches us by radiation.
From the list of options;
option A refers prevention of heat transfer by radiation
option B refers to noodles rising and falling in a poy of boiling water. The path which the noodles move shows the convective path of the fluid.
option C refers to heat transfer by conduction
Option D refers to oth convection and radiation as modes of heat transfer.
option B best describes heat transfer by convection
Answer : 18.22 meters
Explanation:
1 yard. = 0.9144 meters
85.4 yards = 78.08976 meters
1 minute = 60 seconds
5 minutes = 300 seconds
Speed of Anisa = distance / time
Speed of Anisa = 78.08976 meters / 300 seconds
Speed of Anisa = 0.26029 meters / second.
Distance travelled in 70 seconds = speed * 70
Distance travelled in 70 seconds = 0.26029 * 70 = 18.22 meters
