density = mass/volume. so you need to know the mass and the volume.
Given that,
The acceleration of gravity is -9.8 m/s²
Initial velocity, u = 39.2 m/s
Time, t = 2 s
To find,
The final velocity of the shot.
Solution,
Let v is the final velocity of sling shot. Using first equation of motion to find it.
v = u +at
Here, a = -g
v = u-gt
v = (39.2)-(9.8)(2)
v = 19.6 m/s
So, its velocity after 2 seconds is 19.6 m/s.
Answer:
minimum initial velocity is 21.35 m/s
Explanation:
given data
distance S = 30 m
height h = 30 m
maximum acceleration a = 2 m/s²
to find out
minimum initial velocity that your friend could have thrown the object to enable you to catch
solution
first we get here time with the help of second equation of motion
time =
..................1
put her value we get
time = 
time = 5.477 second
and that is time which tossed object must be take so we apply here again second equation of motion that is
-S = ut - 0.5 × gt² .......................2
-30 = u× 5.477 - 0.5 ×9.8×5.477²
solve it we get
u = 21.35 m/s
so minimum initial velocity is 21.35 m/s
Explanation:
PE= mgh
6 J= (3m) (9.81 m/s2) (mass)
mass=( 6)/(3×9.81)
mass= 0.20 Kg
Answer:
b. 40V , 40V
Explanation:
Connections are as per the figure.
As total current through source is 4A , current through each lamp is 1A.
As total resistance of the circuit is 10Ω ,resistance of each bulb is 40Ω because in case of a parallel circuit in which identical objects are connected ,
where R is the resistance of each bulb and n is the number of bulbs.
As per Ohm's law , voltage of the source =IR = 4×10 =40V.
We can see from the figure that if the voltage across the source is 40V , the voltage across each bulb is also 40V.