Answer;
B. both a non-directional and directional hypothesis
Explanation;
A two-tailed test is the standard test of significance to determine if there is a relationship between variables in either direction. Two-tailed tests do this by dividing the .05 in two and putting half on each side of the bell curve.
A non-directional hypothesis is a type of alternative hypothesis used in statistical significance testing. In contrast, a directional alternative hypothesis specifies the direction of the tested relationship, stating that one variable is predicted to be larger or smaller than null value, but not both.
Answer:
Factors that affect the strength of electromagnets are the nature of the core material, strength of the current passing through the core, the number of turns of wire on the core and the shape and size of the core.Nov 28, 2020
Explanation:
Gravitational force on a satellite is given by the formula

now here we know that force on the satellite is F when its distance from center of Earth is R
Now the distance from the center of earth will be 3R so the force is given as


so if we compare it with initial value of force then it is

so correct answer is

Answer:
5.3 nC
Explanation:
The initial charge stored on the capacitor is given by:
(1)
where
is the capacitance of the capacitor
is the potential difference across the capacitor
Substituting numbers into the equation, we have

When the Teflon slab is inserted between the plates, the capacitance of the capacitor is increased as follows:

where k=2.1 is the dielectric constant of the Teflon. Since the voltage V remains constant, this means that the new charge stored by the capacitor (1) will be

and so

Answer:
2.91 x 10¹² sec
Explanation:
d = distance of nearest star, Proxima Centauri = 4.3 ly = 4.3 x 9.46 x 10¹⁵ m
v = speed of new horizon probe = 14 km/hr = 14000 m/s
t = time taken for the new horizon probe to reach nearest star, Proxima Centauri = ?
Using the equation
d = v t
Inserting the values given
4.3 x 9.46 x 10¹⁵ = (14000) t
t = 2.91 x 10¹² sec