If a 20 kg box is accelerating upward at 8 m/s^2 , what is the magnitude of the upward force
1 answer:
Answer:
356 N
Explanation:
Newton's second law of motion describes the relationship between an object's mass and the amount of force needed to accelerate it.
here there is a weight acting downwards on the object , yet it is accelerating upwards shows that there is a net force upwards
Applying Newtons second law of motion upwards ,
Force = mass *acceleration
Upward force - m*g = m *a
F_up= 20 *8 + 20 * 9.8
= 356 N
Upward force= 160 N
You might be interested in
The block is made of A) Tin, as its specific heat capacity is
Explanation:
When an amount of energy Q is supplied to a sample of material of mass m, the temperature of the material increases by , according to the following equation
:
where is the specific heat capacity of the material.
In this problem, we have:
m = 2 kg = 2000 g is the mass of the unknown material
is the amount of energy supplied to the block
is the change in temperature of the material
Solving the equation for , we can find the specific heat capacity of the unknown sample:
And by comparing with tabular values, we can find that this value is approximately the specific heat capacity of tin.
Learn more about specific heat capacity:
#LearnwithBrainly
The energy carried by the incident light is
where h is the Planck constant and f is the frequency of the light. The threshold frequency is the frequency that corresponds to the minimum energy needed to eject the electrons from the metal, so if we substitute the threshold frequency in the formula, we get the minimum energy the light must have to eject the electrons:
where h is the Planck constant and f is the frequency of the light. The threshold frequency is the frequency that corresponds to the minimum energy needed to eject the electrons from the metal, so if we substitute the threshold frequency in the formula, we get the minimum energy the light must have to eject the electrons: