Answer:
Choices A, B, and C are correct.
Explanation:
Let us look at each of the choices one by one:
A. It is a vector
Yes. Velocity is a vector, or it's a speed with direction.
B. It is the change in displacement divided by the change in time.
Yes. The velocity can be written as
where 
is the displacement—a vector quantity.
C. It can be measured in meters per second.
Yes. The units of velocity are m/s, but also with a unit vector indicating the direction.
D. It is the slope of the acceleration vs. time graph.
Nope. The velocity is the slope of displacement vs. time graph.
Hence, only choices A, B, and C are correct.
Answer:
a)
Weight in Air = 0.3N
Weight in Water = 0.25N
Weight in Liquid = 0.24N.
Upthrust /Buoyant Force = Weight in Air – Weight in Fluid(Water in this case)
= 0.3 – 0.25
= 0.5N.
b) R.D of Body = Density of Body/Density of Standard Fluid(Water).
There's a Derived Formula for RD.
I'm gonna Apply it here.
Ask me for the derivation in the Comment section if you need it.
RD = α/ρ = (Weight in Air) / (Upthrust Force)
Where
α = density of the Body(or reference substance)
ρ = density of standard fluid (water)
= 0.3/0.05 = 6.
c) RD of Liquid = (Density of Liquid) /(Density of standard Fluid(water)
Or we just go by that formula
RD of Liquid = Weight in Air/Upthrust(In Liquid)
We'll be using the Upthrust in that Liquid now.
= 0.3 – 0.24 = 0.06
RD = 0.3/0.06 = 5.
Answer: B. A gravitational field
Explanation:
Surrounding earth is gravitational field. Gravitational field is a region of space were gravitational force can be felt and gravitational force is the gravitational pull on the surface of the earth. The presence of this gravity is what allow us to be able to walk freely without falling. It also make us jump up and be able to land back on the ground. Assuming there are no force of gravity in the surface of the earth, there won't be any possibility of landing back on the ground after jumping.
Answer:
F = 104.832 N
Explanation:
given,
upward acceleration of the lift = 1.90 m/s²
mass of box containing new computer = 28 kg.
coefficient of friction = 0.32
magnitude of force = ?
box is moving at constant speed hence acceleration will be zero.
Now force acting due to lift moving upward =
F = μ m ( g + a )
F = 0.32 × 28 × ( 9.8 + 1.9 )
F = 104.832 N
hence, the force applied should be equal to 104.832 N
Answer:
Can a room be gravitationally shielded? No, it can't.
Explanation:
the room cannot be gravitationally shielded because there is only one gravitational charge, in this case is mass. Mass can always be positive. the room can be electrically shielded because there are two type of charge, positive and negative charge than can cancel each other out.
