Choice-A is the correct one. It doesn't say it, but it means he'll see the ball reach the catcher's mitt first BEFORE HE HEARS IT slap the mitt.
Answer:
6.4 J
Explanation:
m = mass of the bullet = 10 g = 0.010 kg
v = initial velocity of bullet before collision = 1.8 km/s = 1800 m/s
v' = final velocity of the bullet after collision = 1 km/s = 1000 m/s
M = mass of the block = 5 kg
V = initial velocity of block before collision = 0 m/s
V' = final velocity of the block after collision = ?
Using conservation of momentum
mv + MV = mv' + MV'
(0.010) (1800) + (5) (0) = (0.010) (1000) + (5) V'
V' = 1.6 m/s
Kinetic energy of the block after the collision is given as
KE = (0.5) M V'²
KE = (0.5) (5) (1.6)²
KE = 6.4 J
<span>Force = Work done / distance = 4Nm / 2m = 2N</span>
Answer:
a) F = 2.25 10³ N, b) REPULSIVE.
Explanation:
a) The electric force is given by coulomb's law
F =
k q1q2 / r2
in this case nso indicate that the two charges have the same value
q₁ = q₂ = 2.5 10⁻⁶ C
Let's reduce the magnitudes to the SI system
r = 0.5 cm (1m / 100cm) = 5 10⁻³ m
let's calculate
F =
F = 2.25 10³ N
b) In electricity, electric charges of the same sign repel and those of the opposite sign attract
In this exercise, the balls are equal and are rubbed with the same material, for which it acquires charges of the same type, consequently, as the charges are of the same type, they indicate that the negative force is REPULSIVE.
Answer:
x=0.154kg
Explanation:
(x*L)+(0.5kg*4200*50)+(x*4200*(-50)=0
(x*333 000J/kg*c)+(0.5kg*4200J/kg*C*(-40C))+(x*4200J/kg*C*50C)=0