Answer:
a = 1 m/s²
Explanation:
given,
mass of the person = 60 Kg
Net External force exerted = 90 N
force of friction opposing the motion = 30 N
acceleration of the box = ?
Net force = External force applied - frictional force
Net force = 90 - 30
net force = 60 N
we know
F = mass x acceleration
60 = 60 x a
a = 1 m/s²
acceleration of the box is equal to a = 1 m/s²
They are magnetic
Your welcome;)
Question 1.
- mass = 4500 kg
- potential energy (p.e) = 67500 J
now, we know :
=》

=》

=》

=》

=》

note : if we take acceleration due to gravity as 9.8, then height = 1.53 m
Question 2.
- mass = 4500 kg
- kinetic energy = 63000 j
we know,
=》

=》

=》

=》

=》

=》

or
=》

Answer:
Speed = 0.296m/2
Period = 0.203 s
Explanation:
If by 'long' you mean the wavelength of the waves, then the wavelength
.
The frequency
of the waves is 14.8 waves every 3 seconds or
.
Now the relationship between wavelength
, frequency
and speed
of the waves is:

We put in the values
and
and get:
Now the period
is just the inverse of the frequency, or


M = mass of aluminium = 1.11 kg
= specific heat of aluminium = 900
= initial temperature of aluminium = 78.3 c
m = mass of water = 0.210 kg
= specific heat of water = 4186
= initial temperature of water = 15 c
T = final equilibrium temperature = ?
using conservation of heat
Heat lost by aluminium = heat gained by water
M
(
- T) = m
(T -
)
(1.11) (900) (78.3 - T) = (0.210) (4186) (T - 15)
T = 48.7 c