How hot or cold something is
How much heat is absent (measuring the absence if heat)
(Fun fact- there is no cold just absence of heat
Answer: I am so sorry i hadn't learned this Yet~!
Explanation:
What physical properties of nylon and leather make them good materials to use for shoelaces? A. high density and low conductivity B. durability and flexibility C. hardness and durability D. low viscosity and flexibility.
Answer:
a) 2.7s
b) 29 m/s
Explanation:
The equation for the velocity and position of a free fall are the following
-(1)
- (2)
Since the hot-air ballon is <em>descending </em>at 2.1m/s and the camera is dropped at 42 m above the ground:


To calculate the time which it takes to reach the ground we use eq(2) with x=0, and look for the positive solution of t:

t = 2.71996
Rounding to two significant figures:
t = 2.7 s
Now we calculate the velocity the camera had just before it lands using eq(1) with t=2.7s
v = -28.782 m/s
Rounding to two significant figures:
v = -29 m/s
where the minus sign indicates the downwards direction