Answer:
D.
a control group
Explanation:
In a scientific experiment such as the one above, there is an experimental group and a control group. The experimental group is the group that receives the treatment while the control group does not receive any treatment. The control group helps the researcher to observe if the treatment had any significant effect.
In this case, it will help Alan and Monica to determine if fertilizer X actually had an effect on the plant. Therefore, the pot with o grams of fertilizer in it is the control group.
Answer:
Thermal energy.
Explanation:
We know that energy is conserved and it only transform one form to another form ,Like potential energy transform in to kinetic energy when a ball fall down from a height and obtain some velocity.
In this case energy changes from gravitational energy to kinetic energy then elastic energy and after some time this energy will convert in to thermal energy.
So the answer is thermal energy.
Answer:
11.5 m
Explanation:
First, find the time it takes to land.
Given:
Δy = -1.5 m
v₀ = 10 sin 37° m/s
a = -9.8 m/s²
Find: t
Δy = v₀ t + ½ at²
-1.5 m = (10 sin 37° m/s) t + ½ (-9.8 m/s²) t²
-1.5 = 6.02 t − 4.9 t²
4.9 t² − 6.02 t − 1.5 = 0
Solve with quadratic formula:
t = [ -(-6.02) ± √((-6.02)² − 4(4.9)(-1.5)) ] / 2(4.9)
t = 1.44
Now find how far it moves horizontally in that time:
Given:
t = 1.44 s
v₀ = 10 cos 37° m/s
a = 0 m/s²
Find: Δx
Δx = v₀ t + ½ at²
Δx = (10 cos 37° m/s) (1.44 s) + ½ (0 m/s²) (1.44 s)²
Δx = 11.5 m
The cat lands 11.5 meters from the table.
Answer:
Wavelength of sound in meters = 1.348 m
Explanation:
Given
speed of sound = 34500 cm
= 345 m (since 1 cm = 0.01m)
frequency of sound = 256 Hz = 256
Wavelength of sound in meters = ?
We know that all waves have same relationship among speed s, frequency f and wavelength λ, which is given by the equation
v = fλ
Wavelength λ = v/f
= 345 m / 256
=1.348 m
Hence wavelength of sound in meters = 1.348 m
