Answer:
The magnitude of the force, B = 5 Tesla, Up (North) direction
Explanation:
Magnetic force F= Eq where Electric field, E = 750 NC
and charge, q = -70 μC = -7 ×
C
F = 750 × -7 ×
F = 0.0525
But F = qvB; B = 
where B is the magnetic field
= 0.0525 ÷ ( -7 × × 30)
B = 5.0 Teslas
The force on a negative charge is in exactly the opposite direction to that on a positive charge.
Hence the direction of the charge is up (North).
Objects should be cooled before their mass is determined on a sensitive balance because it could damage the balance. Also, because it would give you wrong reading of the mass. Hot objects would warm the air around it. A warm air would expand and would produce convection as it rises causing to give the object a mass that is less than the actual. Another reason would be it would cause instability in the readings, the mass would fluctuate every now and then due to the convection currents around the object. It is always recommended to weigh the masses of objects that are in room temperature.
D. All of the above
At high tide fish will feed among the mangrove roots - rich fishing ground
The trees trap sediment and soil in the river that would flow out to sea which also helps stop erosion
Wildlife utilise almost every part of the tree, with insects and birds, monkeys and lizards in the branches, shrimps and fish in the roots, and snails and clams in the soil
Answer:
–735.17 N
The negative sign indicate that the force is acting in opposition direction to the car.
Explanation:
The following data were obtained from the question:
Mass (m) of car = 782.10 kg
Initial velocity (u) = 7.60 m/s
Final velocity (v) = 3.61 m/s
Time (t) = 4.23 s
Force (F) =?
Next, we shall determine the acceleration of the car. This can be obtained as follow:
Initial velocity (u) = 7.60 m/s
Final velocity (v) = 3.61 m/s
Time (t) = 4.23 s
Acceleration (a) =?
a = (v – u) / t
a = (3.61 – 7.60) / 4.23
a = –3.99 / 4.23
a = –0.94 m/s²
Finally, we shall determine the force experienced by the car as shown below:
Mass (m) of car = 782.10 kg
Acceleration (a) = –0.94 m/s²
Force (F) =?
F = ma
F = 782.10 × –0.94
F = –735.17 N
The negative sign indicate that the force is acting in opposition direction to the car.
Kinetic of automobile
Mass m = 1,250 Kg; V = 11 m/s
Formula: K.E = 1/2 mV²
K.E = 1/2(1,250 Kg)(11 m/s)²
K.E = 75,625 J
Speed required for insect to have the same kinetic energy as automobile
Mass of insect = 0.72 g convert to Kg m = 7.2 x 10⁻⁴ Kg
K.E = 1/2 mV² Derive V =?
V = 2 K.E/m
V = √2(75,625 J)/7.2 x 10⁻4 Kg
V = √2.1 x 10⁸ m²/s²
V = 14,491.34 m/s (velocity of insect)
