Answer:
D. a person pulling a sled.
Explanation:
contact force only occurs when something directly comes in contact with another object.
a. is wrong because that is called magnetic force.
b. gravitational force
c. is an electrical force
W=gm
where g - gravitation
m - mass
w - weight
as gravitation equals to zero, multiplying by 0 gives W=0
It is not possible to tell whether and object is heavy or light
Answer:
Let No be initial no of atoms
N = N0 / 2 after 1 half-life
N = N0 / 4 after 2 half-lives
So after 2 half-lives 20 of the 80 atoms remain
Answer:
1.925 μC
Explanation:
Charge: This can be defined as the product of the capacitance of a capacitor and the voltage. The S.I unit of charge is Coulombs (C)
The formula for the charge stored in a capacitor is given as,
Q = CV ................... Equation 1
Where Q = charge, C = Capacitor, V = Voltage.
Note: 1 μF = 10⁻⁶ F
Given: C = 0.55 μF = 0.55×10⁻⁶ F, V = 3.5 V.
Substitute into equation 1
Q = 0.55×10⁻⁶×3.5
Q = 1.925×10⁻⁶ C.
Q = 1.925 μC
Hence the charge on the plate = 1.925 μC
Answer - true
Explanation-