Answer:
1) 0.51 seconds.
2) 1.45 m/s.
Explanation:
given, height from which cat falls = 1.3 m
we know that, s = ut +
at².
here if we consider cat moment only in downward direction,
intial velocity of cat in downward direction , u = 0.
so, time, t =
.
⇒ t =
= 0.51 seconds.
t = 0.51 seconds.
now, consider cat moment only in forward direction
s = ut , since acceleration is zero in forward direction
⇒ u =
.
so, u =
= 1.45 m/s .
Answer:
wave length is 1.2m
Explanation:
since formula of wave length is v/f
v(speed of sound in air at stp is 300ms^-1)
f(frequency 250hertz)
then wave length is 300÷250 which give 1.2m
J.J. Thomson discovered electrons and noticed that an atom can be divided. Also, he concluded atoms are made of positive cores and negatively charged particles within it.